'™ 


LIBRARY 

OF  THE 

UNIVERSITY  OF  CALIFORNIA. 

GIFT  OK 

MRS.   MARTHA   E.   HALLIDIE. 
Class 


HALLIDIE 


Gas  Engine 

Construction 


A  PRACTICAL   TREATISE   DESCRIBING  THE  THEORY  AND 

PRINCIPLES  OF  THE  ACTION  OF  GAS  ENGINES 

OF  VARIOUS   TYPES 


DESIGN  AND  CONSTRUCTION 

OF   A    HALF    HORSE    POWER 

GAS  'ENGINE 


WITH   ILLUSTRATIONS  OF  THE  WORK  IN  ACTUAL   PROGRESS,  TOGETHER 

WITH  DIMENSIONED  WORKING  DRAWINGS  GIVING  CLEARLY 

THE   SIZES   OF  THE   VARIOUS   DETAILS 


FOR  THE  STUDENT, 

THE  SCIENTIFIC   INVESTIGATOR 

AND   THE   AMATEUR   MECHANIC 


BY 

HENRY  V.  A.  PARSELL, 

MEM.  A.  I.  EE.EC.  ENG. 
AND 

ARTHUR  J.  WEED,  M.E. 


SECOND     EDITION,     REVISED    AND     ENLARGED 

Jt 

NEW   YORK 

NORMAN   W.    HENLEY   &   CO. 

132  NASSAU  STREET 
1902 


COPYRIGHTED,  1900 

BY 

NORMAN    W.   HENLEY   &   CO. 

ALSO 

ENTERED  AT  STATIONER'S  HALL  COURT.  CONDON,  ENGLAND 


All  Rights  Reserved 


HALLIDIE 


COMPOSITION,  ELECTROTYPING  AND  PRINTING 

BY 

MACGOWAN  &  SLIPPER 
NEW  YORK,  N.  Y.,  U.  S.  A. 


PREFACE. 

The  use  of  the  gas  engine  as  a  convenient  and  reliable 
source  of  power  is  rapidly  extending^  and  the  present  wide- 
spread interest  in  horseless  vehicles  is  bringing  the  small 
gas  engine  into  special  prominence  as  a  means  to  their 
propulsion. 

There  are  many  good  books  on  the  gas  engine,  its  theory, 
design,  and  various  forms.  There  are  books  on  various 
mechanical  processes,  turning,  planing,  filing,  etc. ;  books, 
too,  on  how  to  make  model  boats,  engines,  locomotives  and 
a  host  of  mechanical  toys,  but  no  really  practical  book  tell- 
ing how  to  make  one  good  machine'and  to  make  it  well.  It 
is  with  the  above  points  in  view  that  the  authors  have 
endeavored  to  give  the  amateur  in  this  book:  first,  a  broad 
and  thorough  knowledge  of  the  principles  of  various  forms 
of  gas  engines ;  second,  a  full  and  concise  description  of  the 
making  of  a  regular  gas  engine  by  practical  shop  methods, 
avoiding  the  makeshifts  and  bungling  so  prevalent  in  the  toy 
machine  books  ;  third,  a  set  of  modified  rules  for  designing 
similar  engines,  followed  by  a  guide  list  of  books  and 
periodicals  useful  to  the  student. 

In  preparing  this  work  for  the  amateur  the  authors  have 
departed  somewhat  from  the  conventional  method  so  long 
in  vogue,  of  illustrating  the  book  with  a  few  pen  drawings 
and  then  calling  on  the  reader's  imagination  to  spread  these 
drawings  over  a  long  and  minute  specification  of  the  neces- 
sary procedure. 


PREFACE. 

We  felt  that  to  give  drawings  of  the  different  parts  and 
follow  this  with  a  lengthy  description  of  each  process  was 
not  the  best  method  to  employ  in  dealing  with  the  construc- 
tion of  this  engine. 

Photographs  were  therefore  taken  of  each  important  ope- 
ration as  it  was  performed  in  building  the  original  engine, 
and  cuts  were  made  directly  from  these  photos. 

As  must  be  supposed  some  of  the  pictures  were  made 
under  very  unfavorable  circumstances,  with  poor  light,  etc., 
but  it  was  necessary  to  make  them  at  that  particular  time  or 
not  at  all.  We  think  this  mode  of  illustration  will  be  appre- 
ciated by  the  amateur  builder. 

The  great  convenience  of  the  angle  plate  as  a  lathe  acces- 
sory is  too  little  known,  and  so  we  have  dwelt  upon  its  uses 
more  extensively  than  would  be  necessary  in  a  book 
addressed  only  to  expert  machinists. 

To  any  who  may  think  it  is  necessary  to  have  a  complete 
machine  shop  at  one's  disposal  in  order  to  construct  one  of 
thes3  engines,  we  need  only  say  that  this  original  engine  was 
built,  and  all  the  photos  of  the  work  made  at  Schroon  Lake, 
in  the  heart  of  the  Adirondacks. 

We  are  indebted  for  the  originals  of  the  rules  of  designing 
to  the  Treatise  on  the  Gas  Engine  published  by  the  Colliery 
Engineer  Co.,  and  also  to  the  excellent  little  Gas  Engine 
Handbook,  by  E.  W.  Roberts. 

The  authors  will  feel  well  repaid  for  the  year's  work  spent 
on  this  book  if  it  advances  the  standard  of  amateur  work- 
manship and  aids  the  reader  and  student  to  find  in  the  con- 
struction of  the  model  gas  engine  a  useful,  practical  and 
pleasant  mechanical  exercise. 

HENRY  V.  A.  PARSELL,  JR. 

June,  1900*  ARTHUR  J.  WEED. 


PREFACE   TO    THE    SECOND    EDITION. 

The  authors  gladly  take  the  opportunity  here  afforded  to 
thank  their  readers  for  the  many  kind  words  of  apprecia- 
tion of  this  work  which  they  have  sent  us  from  time  to 
time.  We  thank  them  also  for  their  pertinent  suggestions, 
which  are  always  welcome. 

In  this  new  edition  we  have  embodied  the  good  things 
that  these  suggestions  and  our  experience  have  shown 
advisable,  and  also  have  corrected  the  few  errors  which 
had  crept  in  undiscovered  until  the  book  was  published. 

The  principal  additions  are  those  showing  the  vertical 
adaptation  of  this  type  of  construction,  the  making  of  cast 
iron  piston  rings  and  the  new  electric  igniter.  We  are 
indebted  to  the  kindness  of  Mr.  E.  J.  Stoddard,  the  well- 
known  gas  engine  expert,  for  the  formula  for  weight  of  fly- 
wheel which  we  give  in  this  edition. 

With  best  wishes  of  success  to  our  amateur  friends,  we 
remain, 

Very  cordially, 

HENRY  V.  A.  PARSELL, 
'ARTHUR  J.  WEED. 


TO 

HENRY  V.  PARSELL,  SR. 

WHOSE   KINDNESS   AND   GENEROSITY 

HAVE   BEEN   OF   GREAT   ASSISTANCE   TO   THE   AUTHORS 
IN     THE     PREPARATION     OF     THIS     WORK 


CONTENTS. 


CHAPTER  I. 
How  the  Gas  Engine  Works, 

PAGE 
9 

CHAPTER  II. 
The  Four  Classes  of  Engines,   . 

17 

Design  of  a  Small  Gas 

CHAPTER  III. 

CHAPTER  IV. 

49 

Pattern  s  —  Continued  , 
Patterns—  Concluded, 

CHAPTER  V. 

59 

CHAPTER  VI. 

.         .         .           67 

Special  Tools, 

CHAPTER  VII. 

.      81 

Cylinder,  etc.,    . 

CHAPTER  VIII. 

91 

Piston,    . 

CHAPTER  IX. 

.    103 

Connecting  Rod, 

CHAPTER  X. 

119 

Bearings,  etc., 

CHAPTER  XI 

•     133 

8  CONTENTS. 

CHAPTER  XII.  PAGE 

Side  Rods,  ....         .         .         .         149 

CHAPTER  XIII. 
Bed  Plate, 157 

CHAPTER  XIV. 
Fly-wheels  and  Shaft,          .          .         .         .         .-.         .         .         161 

CHAPTER  XV. 
Cylinder  Head,       .         .         .         . 173 

CHAPTER  XVI. 
Inlet  Valve,        ..........         183 

CHAPTER  XVII. 
Exhaust  Valve,       .         .         .         .         .         .         .         .         .         .199 

CHAPTER  XVIII. 
Valve  Gearing,     .         .         .         .          .         .         .         .         ,         .211 

CHAPTER  XIX. 

Governor,          .         .         .         .         .          .         .         .         .         m        .217 

CHAPTER  XX. 
Igniter  and  Electrical  Connections,     .          .         .         .         .         .225 

CHAPTER  XXI. 
Assembling,    ...........  233 

CHAPTER  XXII. 
Regulating  and  Starting,    .          .          .          .         .         .         .         .        243 

CHAPTER  XXIII. 
Carbureters,    .         .         .         .          .          .         .  .         .         .251 

CHAPTER  XXIV. 
Engine  Details  and  their  Design, 259 

CHAPTER   XXV. 
Vertical  Engine 235 

CHAPTER   XXVI. 

Annotated  Bibliography  of  the  Principal  Gas  Engine  Books  and 
Periodicals  Published  in  the  English  Language,         .  291 


Chapter    I. 
HOW   THE   GAS   ENGINE   WORKS. 

AN   ELEMENTARY   EXPLANATION. 


GAS  ENGINE  CONSTRUCTION. 


CHAPTER    I. 

HOW   THE    GAS   ENGINE    WORKS. 

Every  one  knows  that  when  a  metal  rod  is  heated  it 
becomes  longer — as  a  matter  of  fact,  it  also  gets  a  little 
broader  and  a  little  thicker. 

So  it  ensues  that  an  iron  bar  is  larger  when  warm  than 
when  cold.  But,  notwithstanding  its  increase  in  size,  it 
will  be  found  on  trial  that  it  weighs  just  the  same  hot  as 
when  cold.  Hence  comes  the  paradox  that  an  iron  bar  of 
a  certain  size  will  weigh  the  same  as  one  a  little  smaller,  the 
key  to  this  lying  in  their  difference  of  temperature.  Now, 
to  explain  this  increase  in  size  without  increase  in  weight 
scientists  have  found  that  the  heat  which  anything  has  is  due 
to  the  vibrating  motion  of  the  tiny  atoms  of  which  it  is  com- 
posed ;  when  cold  the  vibrations  are  somewhat  less  than 
when  hot,  so  the  hotter  the  body  is  the  more  room  the  atoms 
will  take  up  by  their  movements  and  the  larger  it  will  be  to 
us,  our  sense  being  far  from  delicate  enough  to  detect  any- 
thing more  than  the  increase  in  size  of  the  entire  collection 
of  atoms,  that  is,  of  the  whole  body. 

Now  air  or  any  gas  expands  when  heated  very  much  the 
same  as  the  metal  explained  above,  but,  not  being  a  solid 


12  GAS   ENGINE   CONSTRUCTION. 

bocly,  we  only  consider  the  increase  in  volume  of  a  gas,  and 
not  its  increase  in  length,  breadth  or  thickness. 

To  get  work  done  by  the  expansion  of  air  or  any  gas  we 
must  make  it  push  on  something  ;  so,  to  do  this,  we  put  the 
air  in  a  cylinder  which  is  closed  at  one  end  and  provided  with 
a  sliding  piston  at  the  other.  The  next  thing  is  to  get  heat 
into  the  air ;  an  obvious  way  is  to  put  fire  around  the  closed 
end  of  the  cylinder;  the  flame  will  heat  the  cylinder,  which, 
in  its  turn,  will  heat  the  air,  and  the  hotter  the  air  gets  the 
harder  will  its  vibrating  atoms  beat  against  the  inside  of 
the  cylinder,  until- there  is  pressure  enough  to  overcome  the 
friction  of  the  piston  and  the  pressure  of  the  atmosphere, 
and  the  piston  will  move  toward  the  open  end  of  the  cylin- 
der. As  this  is  done  the  pressure  will  become  less  and  less 
in  the  cylinder,  for  the  same  amount  of  air  is  inside  and  at  the 
same  heat,  but  it  now  has  more  room.  So  now  we  have 
arrived  at  a  point  where  the  pressure  of  the  hot  air  is  so 
low  that  it  will  not  push  the  piston  along  any  farther,  and 
we  want  to  get  the  piston  back  and  begin  over  again.  This 
might  be  done  by  taking  away  the  fire  and  running  cold 
water  over  the  end  of  the  cylinder,  thus  cooling  the  air, 
which  would  contract  to  its  original  volume,  and  the  pres- 
sure of  the  outside  air  would  force  the  piston  back. 

The  kind  of  engines  known  as  "  hot-air "  or  "  caloric  " 
engines  are  worked  somewhat  on  this  principle,  only,  instead 
of  applying  fire  and  cold  water  alternately  to  the  end  of  the 
cylinder  they  are  arranged  at  each  end  of  a  closed  cylinder, 
to  which  the  cylinder  containing  the  power  piston  is  con- 
nected by  a  short  tube  of  ample  diameter. 

Fig.  i  shows  such  an  arrangement.  A  is  the  u  working  cyl- 
inder" having  under  it  the  flame  Ft  and  at  the  upper  end  the 
water-jacket  £,  which  consists  of  a  hollow  space  around  the 
cylinder  filled  with  running  water  supplied  by  a  pump 


HOW    THE    GAS   ENGINE   WORKS.  13 

f 

worked  from  the  beam,  but  not  shown  in  the  figure.  B  is 
the  power  cylinder,  with  its  piston  D  connected  to  the 
crank  H.  Operated  from  this  satne  crank  through  the  beam 
G,  and  connecting  rods  J  and  K,  is  the  plunger  C.  This 
plunger  moves  freely  up' and  down  in  the  cylinder  A,  and  its 


FIG.  i. — HOT  AIR  ENGINE. 

use  is  to  cause  the  air  in  A  and  B  to  be  alternately  heated 
and  cooled  so  as  to  work  the  engine.  A  description  of  the 
action  during  one  revolution  will  make  things  clear. 

As  will  be  seen,  the  plunger  C  is  at  the  top  of  its  stroke ; 
this  keeps  the  enclosed  air  down  in  the  hot  end  of  the  cylin- 
der, and  as  it  expands  it  pushes  the  piston  D  outward,  as 
shown  by  the  arrow  above  cylinder  B.  When  D  gets  near 


14  GAS   ENGINE   CONSTRUCTION. 

* 

the  outer  end  of  its  stroke  the  crank  H  will  be  rising  and, 
consequently,  the  plunger  C  will  move  down,  forcing  the 
hot  air  up  to  the  part  of  the  cylinder  kept  cool  by  the  water- 
jacket.  At  this  time  the  piston  D  is  beginning  the  inward 
stroke  (motion  of  the  parts  being  kept  up  by  the  fly-wheel  /), 
and  the  air  in  the  upper  part  of  A  gives  up  its  heat  to  the 
running  water  and,  by  cooling,  contracts.  The  pressure  in 
B  being  thus  diminished,  the  piston  D  is  forced  in  by  the 
pressure  of  the  outer  atmosphere.  When  at  the  inner  end 
of  the  stroke  of  D,  the  plunger  C  will  rise  and  shift  the  air 
down  to  the  hot  end  of  the  cylinder  so  as  to  expand  it  again, 
and  thus  a  continuous  action  of  the  machine  is  maintained. 

These  caloric  engines,  while  running  very  nicely,  are  too 
cumbrous  when  used  for  large  powers  and  would  require  a 
large  amount  of  water  to  cool  the  air.  Their  principal  use 
is  for  pumping  water,  and  thus  by  their  own  work  make 
available  the  water  which  otherwise  might  be  wasted. 

Now,  the  simplest  of  ways  to  bring  heat  to  air  in  a  cylin- 
der is  to  mix  in  with  the  air  a  little  gas  or  oil  vapor,  just 
enough  being  put  in  to  be  completely  burned  by  the  amount 
of  air  in  the  cylinder,  and  then  start  the  combustion  of  the 
mixture  by  a  spark.  Instantly  the  whole  charge  in  the  cyl- 
inder is  filled  with  a  blaze  and  the  pressure  will  rise  from  that 
of  the  atmosphere,  15  pounds  per  square  inch,  to  75  or  80 
pounds  per  square  inch,  and  the  piston  will  move  outward 
with  great  force.  This  sudden  rise  of  pressure  is  due  to  the 
rapid  heating  of  the  whole  body  of  air  by  the  burning  of  the 
inflammable  gas  mixed  with  it.  There  is,  in  fact,  a  veritable 
explosion,  but  since,  in  an  actual  engine,  the  piston  travels 
out  under  control  of  the  crank  and  fly-wheel,  the  explosion 
is  not  perceived  except  as  a  strong,  rapid  push  on  the  pis- 
ton. This,  then,  is  the  principle  of  action  of  a  gas  engine 
and,  from  the  nature  of  the  motive  force,  gives  rise  to  the 


HOW   THE    GAS   ENGINE   WORKS.  1 5 


• 


names  "  explosion  engine "  and  "  internal  combustion 
engine  "  by  which  it  is  also  frequently  called.  The  second 
name,  "  internal  combustion  engine,"  is  the  most  general,  and 
scientifically  correct,  as  it  refers  to  any  engine  driven  by 
gas,  gasoline  or  petroleum  mixed  with  air  in  a  cylinder  and 
there  consumed. 

Historically  considered,  the  internal  combustion  engine 
may  be  said  to  have  originated  with  the  invention  of  gun- 
powder, for  the  action  in  every  rifle  or  cannon  is  that  of  a 
rapid  chemical  combination  or  combustion  which  evolves  a 
great  quantity  of  gaseous  matter,  the  confinement  of  which 
in  the  gun  barrel  produces  a  great  pressure  on  the  projectile 
— or  freely  moving  piston — and  propels  it  with  a  high 
velocity. 

A  gunpowder  engine  was  built  by  the  Abbe  de  Hautefe- 
uille  in  1678.  It  was  the  same  in  principle  as  modern  gas 
engines,  except  that  no  air  inlet  was  needed,  the  ignition  of 
the  powder  setting  free  the  oxygen  in  its  composition  in  a 
quantity  sufficient  for  its  own  combustion,  the  same  as  in  the 
case  of  the  gun  cited  above. 

Over  a  hundred  years  elapsed  before  the  first  actual  gas 
engine  was  patented  in  England  by  John  Barber,  in  1791. 
In  France  the  first  patents  were  issued  to  Philippe  Lebon  in 
1799  and  1801.  His  engine  was  very  ingenious  and  included 
a  frictional  electric  machine  to  ignite  the  explosive  charge. 
The  assassination  of  Lebon,  in  1804,  put  an  end  to  the  per- 
fecting of  his  invention. 

In  1833  a  double  acting  engine  having  pumps  to  separately 
compress  the  gas  and  air  and  inject  them  into  the  power 
cylinder  was  brought  out  by  Wright,  but  the  rapid  intro- 
duction of  steam  power  at  the  same  period  diverted  public 
attention  from  this  motor. 

Various  patents  were  taken  out  between  this  time  and 


l6  GAS   ENGINE   CONSTRUCTION. 

1860,  when  the  Lenoir  engine  appeared  and  created  con- 
siderable enthusiasm  for  the  gas  engine  by  its  smooth  and 
regular  operation.  It  was  a  double-acting  engine  of  the  first 
class  as  described  in  the  next  chapter.  Its  lack  of  economy, 
as  compared  with  steam,  soon  caused  its  disappearance  from 
extended  service.  The  first  of  the  modern  types  of  highly 
efficient  engines  was  brought  out  by  Otto  in  1878.  This 
marks  the  practical  introduction  of  the  principle  which  has 
given  rise  to  what  is  now  a  large  industry,  with  almost 
countless  modifications  of  details  as  designed  by  the  man} 
inventors  who  have  been  engaged  during  the  past  twenty 
years  in  this  work. 


Chapter  II. 
THE   FOUR   CLASSES   OF   ENGINES. 

THE  CROWN  GAS   PUMP.      THE   BRAYTON   ENGINE.      THE   OTTO 
CYCLE.     GOVERNING  OF  THE  OTTO  ENGINE.     TWO,  THREE 
AND    FOUR    CYLINDER     ENGINES.        DOUBLE    ACTING 
ONE      AND      TWO      CYLINDER      ENGINES.         TWO 
CYCLE    ENGINES   OF   ONE    AND    TWO    CYLIN- 
DERS.     THE   DIESEL  ENGINE.      DESCRIP- 
TION  OF   THE    MODEL   ENGINE. 


CHAPTER  II. 


THE   FOUR    CLASSES   OF    ENGINES. 

The  modes  of  utilizing  the  principle  of  explosion  can  be 
conveniently  divided  into  four  classes,  which  are  here  given 
with  explanations  of  their  actions. 

CLASS  i.     The    piston,    traveling    outward,    see    Fig.    2, 


FIG.  2. — DIAGRAM  OF  CLASS  I. 

draws  in  a  mixed  charge  of  gas  and  air  until  it  reaches  about 
half  of  its  full  stroke.  At  this  point  the  inlet  valves  are 
closed,  and  a  spark  is  used  to  ignite  the  mixture  whose  com- 
bustion and  expansion  now  drive  the  piston  forcibly  out  to 
the  end  of  its  stroke.  The  exhaust  valve  then  opens,  and 
the  products  of  combustion  pass  out  during  the  entire 
return  stroke. 

It  is  obvious,  that  since  the  volume  of  the  explosive  mix- 
ture is  but  half  the  total  contents  of  the  cylinder,  and  that 
the  force  of  the  explosion  acts  on  the  piston  during  but  half 
a  stroke,  therefore,  this  class  of  engine  must  be  very  cumber- 
some compared  with  more  efficient  types.  This  objection 


20 


GAS   ENGINE   CONSTRUCTION. 


U 
fa 

o 
w 


THE    FOUR    CLASSES    OF    ENGINES.  21 

t 

was  met  by  making-  the  engine  double-acting,  that  is,  by 
using  a  piston  and  piston  rod  like  those  in  a  steam-engine, 
and  admitting  the  mixture  at  both  ends  of  the  cylinder  alter- 
nately, but  even  when  made  in  this  way  the  engine  used 
about  six  times  as  jnuch  gas  per  horse  power  as  a  good 
modern  engine. 

Despite  the  inefficiency  of  engines  of  Class  i,  their  sim- 
plicity, when  single  acting,  has  continued  them  in  use  for 
small  domestic  work  where  the  cost  of  running,  being  so 
little,  is  not  considered. 

The  Crown  gas  pump,  Fig.  3,  is  a  good  example  of  this 
class.  The  piston-rod  operates  the  pump  piston  through  the 
bell  crank  seen  to  the  right  of  the  air  chamber,  the  pump 
cylinder  is  vertical  and  hangs  below  the  engine  bed.  The 
water  from  the  pump  is  used  to  keep  the  cylinder  cool  by 
passing  through  a  hollow,  annular  space  cast  in  it. 

The  admission  and  the  flame  ignition  are  controlled  by  two 
cylindrical  valves  operated  by  eccentrics.  There  is  no  gov- 
ernor, as  the  load  is  always  present. 

CLASS  2.  Two  cylinders  are  used,  as  shown  in  the  diagram, 
Fig.  4,  one  being  an  air  pump  P,  the  other  the  working  or 
power  cylinder  C.  The  cylinders  are  both  of  the  same 
diameter  and  are  connected  by  an  intermediate  chamber, 
the  receiver  R.  The  stroke  of  the  piston  of  the  air-pump 
is  but  half  that  of  the  piston  of  the  power  cylinder,  this  ratio 
being  preserved  by  the  positions  of  the  points  of  attachment 
of  their  connecting  rods  to  the  working  beam  B  with  re- 
spect to  the  fulcrum  of  the  beam  at  D. 

The  operation  is  as  follows  : — the  air-pump  piston,  ascend- 
ing, draws  in  a  charge  of  gas  and  air.  On  its  down  stroke 
the  charge  is  forced  into  the  receiver,  through  which  it 
passes  into  the  cylinder  C  by  a  valve  Fand  a  plate  of  wire 
gauze  G.  On  entering  the  cylinder  the  mixture  is  at  once 


22 


GAS   ENGINE   CONSTRUCTION. 


ignited  by  the  small  flame  F,  which  is  maintained  by  a  jet 
of  the  mixture,  which  is  allowed  to  flow  through  a  by-pass 
around  the  valve  V.  The  expansion  of  the  burning  mixture 
as  it  flows  into  C,  forces  out  the  piston  until  the  end  of  the 
stroke  is  reached,  when  the  exhaust  valve  opens  and  the  de- 
scending piston  forces  out  the  burnt  gases,  the  air-pump,  at 
the  same  time,  drawing  in  a  fresh  charge. 

The  object  of  the  plate  of  wire  gauze  G  is  to  prevent  the 


FIG.  4. — DIAGRAM  OF  CLASS  II. 

flame  in  Cfrom  igniting  the  inflammable  mixture  in  R.  This 
it  does  in  the  same  way  that  the  gauze  in  a  miner's  safety 
lamp  prevents  its  flame  from  exploding  the  dangerous 
vapors  so  often  present  in  mines.  Engines  of  this  type, 
though  fifty  per  cent,  more  efficient  than  those  of  Class  i, 
are  not  now  in  use. 

CLASS  3.  This  being  the  class  of  engine  most  largely  used, 
as  well  as  the  kind  whose  construction  is  the  principal  sub- 
ject of  this  book,  we  will  describe  its  operation  more  par- 
ticularly. 


THE   FOUR   CLASSES   OF   ENGINES.  23 

f 

The  cylinder  and  valves,  shown  in  Fig.  5,  are  about  the 
same  as  shown  for  Class  i,  but  the  piston,  in  drawing  in  a 
charge,  goes  the  full  length  of  its  stroke  and  so  gets  a  whole 
cylinder  full  of  mixture — twice  as  much  as  in  Class  I.  Now 
the  piston  moves  in  and  compresses  the  charge  into  the  rear 
part  of  the  cylinder,  called  the  combustion  chamber,  which 
has  a  volume  equal  to  about  one-third  of  the  volume  of  the 
cylinder  when  the  piston  is  at  the  outer  end  of  its  stroke. 

The  igniter  now  operates,  while  the  crank  is  passing  the 
dead  center,  and  suddenly  the  pressure  rises,  reaching  per- 
haps as  much  as  250  pounds  per  square  inch.  The  piston 


.  5. — DIAGRAM  OF  CLASS  III. 

has  now  started  on  its  forward  journey  and  the  gases  under 
pressure  push  it  along,  at  the  same  time  expanding  and  los- 
ing their  pressure.  At  the  outer  end  of  the  stroke  the  pres- 
sure will  have  fallen  to  about  40  pounds.  Now  the  exhaust 
valve  is  opened  and  the  burnt  charge  passes  out  during  the 
in-stroke  of  the  piston. 

The  curves  around  the  crank  in  Fig.  5  show  the  action  at 
different  parts  of  the  revolution  ;  first — the  suction  during 
half  a  turn  ;  second — compression  for  another  half  turn,  the 
ignition  now  spreads  its  flame  through  the  mixture  ;  third — 
the  expansion  of  the  hot  gases  ;  fourth — their  exhaust,  begin- 
ning just  a  little  before  the  end  of  the  second  out-stroke,  so 


24  GAS   ENGINE   CONSTRUCTION. 

that  there  will  be  no  back-pressure  on  the  piston  during  its 
return. 

From  the  above  it  will  be  seen  that  there  is  but  one 
impulse — one  explosion — to  every  four  strokes  of  the  piston. 
On  this  account,  engines  working  in  this  way  are  called  four- 
cycle engines. 

This  cycle  of  operations  was  first  proposed  by  a  French 
scientist,  Beau  de  Rochas,  in  1870.  It  was  not  embodied  in 
a  practical  machine  until  Otto  built  his  first  compression  gas 
engine  in  1876.  From  this  circumstance  the  cycle  came  to 
be  known  as  the  Otto  cycle,  although  the  honor  of  its  inven- 
tion belongs  to  Beau  de  Rochas. 

The  greater  efficiency  of  this  class  of  engine  over  those  of 
Class  i  is  due  to  several  reasons  :— 

First. — A  greater  amount  of  the  explosive  mixture — the 
charge — can  be  drawn  into  a  cylinder  of  given  dimensions, 
and  consequently  more  power  can  be  obtained  from  an  en- 
gine of  certain  size. 

Second  — The  higher  the  pressure  of  the  charge  at  the 
moment  of  ignition,  the  more  rapid  is  the  spread  of  the  flame 
through  the  mixture,  and,  therefore,  it  follows  that  the  ex- 
plosive pressure  is  much  higher  than  if  there  had  been  no 
previous  compression. 

Third. — The  area  of  the  cylinder  walls  which  enclose  the 
charge  at  the  moment  of  its  ignition  is  relatively  less  than  in 
Class  i,  hence  the  burning  gases  cannot  lose  as  much  heat, 
and  consequently  pressure,  through  the  cylinder. 

Fourth. — From  the  above  it  follows  that  the  average  pres- 
sure during  the  power  stroke  of  the  piston  is  much  higher, 
and,  therefore,  more  power  can  be  obtained  from  the  gas. 

As  an  example  of  this  class  we  will  illustrate  the  Otto 
gasoline  engine  with  electric  igniter.  Attached  to  the  mas- 
sive bed  B,  Fig.  6,  is  the  cylinder  A  surrounded  by  a  water 


THE   FOUR  CLASSES   OF   ENGINES.  25 

t 

jacket.    At  the  rear  of  A  is  bolted  the  combustion  chamber  Cf 

also  water-jacketed  by  a  continuation  of  that  on  the  cylinder. 

The    casting  C  carries  the   mixing  chamber  D,  exhaust 


/ 


FIG.  6.— SINGLE  CYLINDER,  SINGLE  ACTING,  FOUR  CYCLE 
GASOLINE  ENGINE  OF  CLASS  III. 

valve  and  casing  E,  and  the  igniter  F,  together  with  the 
levers,  springs,  etc.,  which  operate  them.  The  shaft  at  the 
side  of  the  cylinder  is  geared  so  as  to  make  one  revolution 


26  GAS   ENGINE   CONSTRUCTION. 

while  the  crank  shaft  makes  two,  thus  operating  the  valves 
at  the  proper  times  during  the  cycle. 

The  air  taken  into  the  cylinder  is  first  warmed  by  draw- 
ing it  through  a  chamber  attached  to  the  exhaust  muffler. 
This  warming  is  to  assist  the  air  in  vaporizing  the  gasoline  and 
mingling-  with  it  to  form  a  combustible  mixture.  The  warm 
air  then  passes  through  the  horizontal  pipe  marked  "AIR  " 
to  the  chamber  D.  At  this  same  time  the  liquid  gasoline, 
which  is  supplied  by  a  small  tank  through  the  pipe  N  and 
filter  /,  and  controlled  by  the  cock  J  and  needle  valve  K, 
is  admitted  to  D  by  the  valve  stem  H  being  depressed  by 
the  arm  M  moved  by  a  cam  at  L. 

The  entering  gasoline  is  sprayed  by  the  needle  valve  K 
against  the  perforated  metal  plate  O  shown  in  Fig.  7,  and  is 
at  once  vaporized  and  carried  off  into  the  cylinder  through 
the  inlet  valve  G,  which  lifts  automatically  under  the  power- 
ful suction  of  the  outgoing  piston. 

At  the  outer  end  of  the  stroke  of  the  piston,  as  it  comes 
to  rest,  the  valves  G  and  PI  are  closed  by  their  springs,  so 
that  during  the  compression  stroke  there  can  be  no  escape 
of  the  charge  from  the  cylinder. 

When  the  inner  dead  center  is  reached  and  the  compres- 
sion is  at  its  highest,  then  a  sudden  incline  on  the  cam  P, 
Fig.  6,  lifts  one  end  of  arm  Q,  depressing  its  other  end  and 
thereby  giving  a  slight  rotation  to  the  shaft  fi,  and  causing 
the  electrode  on  its  inner  end,  see  Fig.  7,  to  jump  out  of 
contact  with  the  fixed  electrode  F,  and  thus  producing  a 
spark  by  breaking  a  circuit.  The  electrodes  remain  separ- 
ated until  near  the  close  of  the  compression  stroke,  when 
the  cam  brings  them  gently  into  contact,  which  is  made  firm 
by  the  springs  attached  to  and  acting  on  the  lever  Q, 
Fig.  6. 

When  the  working  stroke  of  the  piston  is  about  finished, 


THE   FOUR   CLASSES   OF   ENGINES.  2/ 

§ 

the  earn  V,  Fig.  6,  depresses  the  lever  5,  whose  other  end 
U  rises  and  lifts  the  exhaust  valve  during  the  second  in- 
stroke  of  the  piston  and  allows  the  burnt  charge  to  pass  out 
down  the  pipe  shown. 

In  order  that  the  starting  of  the  engine  may  be  made  easy, 
the  handle  T  is  moved  to  the  right;  this  throws  in  an  aux- 


FIG.  7.— INLET  VALVES  OF  GASOLINE  ENGINE. 

iliary  cam  which  opens  the  exhaust  valve  during  a  part  of 
the  compression  stroke,  thus  allowing  a  portion  of  the  charge 
to  escape,  so  that  it  is  not  so  hard  to  turn  the  wheels. 

The  governor  V,  through  the  medium  of  the  L-shaped 
lever  W,  Fig.  8,  moves  the  roller  Z,  which  slides  freely  on 
the  stud  N,  along  the  cylinder  C  on  the  side  shaft.  This 


28 


GAS   ENGINE   CONSTRUCTION. 


cylinder  has  a  projecting  cam  D,  which,  when  the  governor 
is  at  its  mid-position,  comes  under  the  roller  L  and  thereby 
rotates  the  rock-shaft  M  and  admits  the  gasoline  as  above 
described. 


w 


FIG.  8. — OTTO  TYPE  OF  GOVERNOR. 

When  the  speed  of  the  engine  rises,  on  loads  less  than  the 
full  capacity  of  the  engine,  the  governor  moves  the  roller  to 
the  left,  so  that  it  is  not  lifted  by  the  cam  D,  and  the  charge 
of  fuel  is  thereby  omitted. 

When  the  engine  is  stopped,  either  from  lack  of  fuel  or 


THE   FOUR  CLASSES   OF   ENGINES. 


29 


too  heavy  an  overload,  the  roller  L  is  carried  to  the  right  of 
cam  D,  so  that,  should  the  oil  cocky\Fig.  6)  be  carelessly 
left  open,  there  could  be  no  escape  of  gasoline  into  the  air 
supply  pipe. 

The  fact  that  there  is  but  one  explosion  to  every  two 


:; 


FIG.  9. — Two  CYLINDER,  SINGLE  ACTING,  FOUR  CYCLE 
ENGINE  OF  CLASS  III. 

revolutions  has  led  to  many  combinations,  more  or  less 
ingenious  and  practiqable,  whereby  the  force  exerted  by 
the  engine  may  be  rendered  more  uniform,  like  that  of  a 
good  steam  engine. 

An  obvious  method   is   to   multiply  the  number  of  cylin- 


GAS   ENGINE   CONSTRUCTION. 


THE   FOUR  CLASSES   OF   ENGINES. 


32  GAS   ENGINE   CONSTRUCTION., 

ders.  Two  cylinders  working  alternately  will  give  one 
impulse  to  each  revolution  of  the  shaft.  A  modern  engine 
of  this  kind  is  shown  in  Fig.  9. 

The  next  step,  the  use  of  three  cylinders,  gives  one 
impulse  to  every  two-thirds  of  a  revolution.  This  type  is 
illustrated  in  Fig.  10. 

The  use  of  four  cylinders,  shown  in  Fig.  n,  is  as  far  as 
this  type  of  stationary  engine  goes,  as  it  gives  two  impulses 


FIG.  12. — DIAGRAM  OF  DOUBLE  ACTING,  FOUR  CYCLE 
CYLINDER  OF  CLASS  III. 

to  each  revolution,   but   experimental   engines   have   been 
built  for  automobiles  with  more  than  four  cylinders. 

In  all  the  above  forms  the  cylinders  are  "  single  acting," 
that  is,  they  force  the  piston  in  but  one  direction  by  the 
action  of  the  explosion.  Now,  if  we  make  each  cylinder 
double  acting  by  closing  both  ends,  and  drive  the  piston  both 
forward  and  backward  by  explosions  alternately  in  opposite 
ends  of  the  cylinder,  we  will  accomplish  in  the  one  cylinder 
what  before  it  took  two  to  do,  and  the  engine  may  thus  be 
made  more  simple. 


THE   FOUR   CLASSES   OF   ENGINES. 


33 


A  sectional  view  of  a  single  cylinder  engine  of  this  type 
is  shown  in  Fig.  12. 

It  will  be  noticed  that  the  water-jacket  is  continued  into 
a  chamber  in  the  cylinder  head,  surrounding  the  piston  rod, 
so  as  to  protect  the  packing  around  the  rod  from  the  heat 
of  the  explosions. 


FIGS.  13  AND  14. — Two  CYLINDER,  DOUBLE  ACTING,  FOUR  CYCLE 
ENGINE  OF  CLASS  III. 

Figs.  13  and  14  show  a  double  acting  double  cylinder 
tandem  engine.  In  this  the  pistons  and  rod  are  hollow  and 
have  a  water  circulation  through  them. 

In  designing  multiple  cylinder  and  other  combined  forms, 
there  are  many  details  of  apportioning  the  explosions  among 
the  cylinders  and  of  balancing  the  pistons,  which  we  cannot, 
in  a  work  of  this  kind,  enter  into. 


34 


GAS   ENGINE   CONSTRUCTION. 


An  important  type  of  engines  of  this  third  class  is  known 
as  the  "  two-cycle." 

In  two-cycle  engines  the  front  end  of  the  cylinder  is  pro- 
longed into  a  closed  chamber  containing  the  connecting  rod 
and  crank.  To  illustrate  its  action  we  will  select  a  simple 
form  shown  in  Fig.  15. 

On  the  up  stroke  of  the  piston  A,  gas  and  air  are  drawn 
through  the  valve  D  into  the  crank  chamber  O.  The  down 
stroke  of  the  piston  now  compresses  this  mixture  until  at 
the  close  of  the  down  stroke  the  upper  end  of  the  piston 


FIG.  15. — DIAGRAM  OF  SINGLE  CYLINDER,  Two  CYCLE 
ENGINE  OF  CLASS  III. 

uncovers  a  passage  (seen  at  the  extreme  right)  leading  from 
the  crank  chamber  O  into  the  cylinder  E.  The  compressed 
mixture  rushes  up  this  passage,  strikes  the  plate  B,  which  is 
cast  on  the  piston,  is  deflected  by  B  to  the  upper  part  of  the 
cylinder  and  forces  the  residue  of  the  previous  combustion 
out  through  the  exhaust  port  K,  which  opens  opposite  the 
charge  inlet  passage. 

The  up  stroke  of  the  piston  now  compresses  the  charge  in 
E  and  at  the  same  time  draws  in  a  fresh  charge  to  the  crank 
chamber. 


THE   FOUR   CLASSES   OF   ENGINES.  35 


• 


At  the  upper  end  of  the  stroke  ignition  takes  place  and 
the  working  stroke  ensues,  compressing  the  new  charge  in 
the  lower  chamber  ready  for  admission  as  soon  as  the  piston 
opens  the  exhaust  and  inlet  ports  again. 

In  this  way  we  get  all  the  advantages  of  the  compression 
used  in  the  cycle  of  Beau  de  Rochas,  and  have  an  impulse 
at  every  revolution. 

The  name  "  two  cycle  "  is  derived  from  the  fact  that  the 
cycle  of  operations  (admission,  compression,  explosion  with 
expansion  and  exhaust)  is  completed  in  two  strokes  of  the 
piston. 

The  absence  of  cam-actuated  valves  will  be  remarked  as 
giving  extreme  simplicity  to  this  type. 

In  Fig.  1 6  is  shown  a  motor  of  this  type.  The  only  exter- 
nal reciprocating  part  is  the  vertical  rod  at  the  right,  which 
operates  the  igniter.  On  the  passage  connecting  the  crank 
chamber  and  cylinder  is  seen  a  valve  whereby  the  speed  can 
be  varied  by  hand. 

When  required,  this  valve  can  be  operated  by  a  governor, 
so  as  to  control  the  speed  of  the  engine  automatically. 

Like  the  four-cycle  type,  this  form  of  engine  can  also  be 
arranged  in  a  large  variety  of  combinations.  We  will  show 
but  a  single  example,  in  Fig.  17.  Here  the  cranks  and  con- 
necting rods  are  open,  but  cylinder  heads,  piston  rods  and 
cross-heads  are  provided,  so  that  the  admission  and  com- 
pression take  place  in  the  lower  end  of  the  cylinder,  the 
ignition  and  expansion  following  in  the  upper  end  as  before. 

This  particular  model,  then,  gives  two  impulses  to  each 
revolution  and  accomplishes  with  its  two  cylinders  what  the 
four-cycle  form  shown  in  Fig.  11,  on  p.  31,  does  with  four. 

Class  4. — This  is  represented  at  present  by  the  motor  of 
but  a  single  inventor,  Herr  Rudolph  Diesel. 

A  sectional  cut  is  shown  in   Fig.  18,  in  which  A   is  the 


30  GAS   ENGINE   CONSTRUCTION. 

cylinder,  B  the  piston,  and  C  the  compression  space,  which 
is  about  6  or  7  per  cento  of  the  cylinder  volume  when  the 
piston  is  at  the  lower  end  of  its  stroke. 

Instead  of  the  trunk  piston   so  common  in  gas  engines, 
there  is  a  shorter  piston  provided    with   the  piston-rod  D, 


FIG.  1 6. — SINGLE  CYLINDER,  Two  CYCLE  ENGINE 
OF  CLASS  III. 

cross-head  K  and  connecting  rod  Ny  which  by  the  crank 
pin  U  turns  the  crank  shaft  5. 

At  P  is  an  air  pump  operated  from  a  point  on  the  connect- 
ing rod  N  by  a  link  and  the  lever  y. 


THE   FOUR   CLASSES   OF   ENGINES.  37 

• 

The  cylinder  A  is  surrounded  by  a  water  jacket  J,  which 
is  continued  into  the  cylinder  head  and  to  the  air  pump  /. 

A  heavy  frame  O  supports  the  cylinder  and  is  bolted  to 
the  bed  plate  Py  which  also  contains  the  crank  shaft 
bearings. 


FIG.  17. — DOUBLE  CYLINDER,  Two  CYCLE  ENGINE 
OF  CLASS  III. 

The  engine  works  on  a  four-stroke  cycle  like  the  Otto,  but 
its  smallcompression  space  and  absence  of  an  igniter  make 
its  action  so  different  as  to  place  it  in  a  separate  class. 

In  order  to  understand  the  action  in  this  engine  it  must  be 


GAS   ENGINE   CONSTRUCTION. 


remembered  that  when  work  is  performed  on  a  gas,  as  by 
compressing  it  in  a  cylinder,  the  temperature  of  the  gas  is 
raised.  So  that  by  compressing  a  body  of  air  in  a  cylinder 
with  sufficient  force  and  quickness,  so  as  not  to  lose  much 
by  radiation,  we  can  raise  its  temperature  very  considerably. 
The  same  principle  is  shown  in  the  familiar  experiment  of 
warming  an  iron  bar  by  placing  it  on  an  anvil  and  rapidly 
hammering  it. 

In  the  Diesel  engine  the  first  down  stroke  of  the  piston 

draws  in  a  charge  of  air  alone,  both 
in  the  cylinder  A  and  in  the  air 
pump/.  On  the  up-stroke  the  air 
in  the  cylinder  is  compress  d  to 
the  pressure  of  500  pounds  per 
square  inch,  and  has,  in  conse- 
quence, the  temperature  of  1200°  F. 
.  The  air  in/  is  brought  to  a  con- 
siderably higher  pressure,  ai  d,  at 
the  end  of  the  up  stroke,  this  air  is 
used  to  blow  into  the  compression 
space  C  a  small  quantity  of  oil, 
which  is  ignited  by  the  high  tem- 
perature of  the  air  in  said  space. 
This  injection  and  combustion  of  the  oil  fuel  continues 
during  one-tenth  of  the  down  stroke,  and  the  expansion  of 
this  hot  gaseous  mass  then  continues  to  the  lower  end  of  the 
stroke,  when  the  exhaust  valve  opens  and  remains  so  during 
the  second  up  stroke.  The  tank  T  and  pressure  gauge  G 
are  used  in  starting  the  engine.  At  q  is  a  mechanical  device 
for  forcing  lubricating  oil  to  the  piston  B. 

As  the  reader  will,  by  this  time,  have  a  good,  general  idea 
of  gas  engine  operation,  we  will,  in  the  next  chapter,  give  a 
little  description  of  the  simplified  type  of  engine  whose 
construction  is  the  subject  of  this  book. 


FIG.    1 8. — DIAGRAM    OF 
ENGINE  OF  CLASS  IV. 


Chapter  III. 
DESIGN   OF   A   SMALL  GAS   ENGINE. 


CHAPTER    III. 

DESIGN    OF  A   SMALL   GAS   ENGINE. 

The  engine  which  this  book  particularly  describes  was 
designed  to  meet  the  requirements  of  the  amateur  needing 
a  small  power,  and  who  wishes  to  build  his  own  engine. 

The  facilities  of  the  amateur  for  engine  construction  are 
necessarily  limited.  Few  of  them  possess  a  planer  or  shaper, 
and  many  are  not  equipped  with  a  screw-cutting  engine 
lathe.  It  is  from  this  point  of  view  that  the  design  and  con- 
struction of  the  parts  of  the  engine  have  been  carefully 
worked  out. 

The  first  engine  constructed  from  this  design  wras,  with 
the  exception  of  the  fly  wheels  and  bed  plate,  built  on  a 
lo-inch  Reed  bench  lathe,  having  a  plain  hand  slide  rest. 

The  engine  can  be  just  as  well  built  on  a  lathe  swinging 
only  8  inches,  as  may  be  seen  from  the  photo-engravings  of 
the  different  lathe  operations. 

The  largest  pieces  which  are  to  be  turned  are  the  cylinder 
collars,  and  they  measure  but  6  inches  across  the  lugs. 

As  will  be  seen  on  examining  the  half-tone  cuts,  Figs  50 
and  53,  the  lo-inch  lathe  is  large  for  the  work.  The  fly 
wrheels  are  something  the  amateur  will  require  to  have  done 
for  him.  These  can  be  procured,  turned  and  finished  at  a 
nominal  price.  The  bed  plate  is  to  be  filed  up  on  the  level 
projections,  where  the  main  bearings  and  cylinder  supports 
rest,  or  this  can  be  supplied  planed  up. 


42  GAS   ENGINE   CONSTRUCTION. 

All  the  other  parts  of  the  engine  are  designed  to  be  built 
up  without  the  necessity  of  planing. 

The  surfacing  of  the  bottoms  of  the  main  bearings  and 
cylinder  supports  is  arranged  for  by  the  use  of  the  angle 
plate  which  is  attached  to  the  face  plate  of  the  lathe,  as  will 
be  seen  in  the  chapter  describing  these  operations. 

The  entire  thrust  of  the  engine  is  transferred  from  the 
piston  to  the  fly  wheels  through  the  connecting  rod,  and  the 
corresponding  back  thrust  between  the  cylinder  and  the 
bearings  is  taken  by  the  two  steel  side  rods,  thus  relieving 
the  cylinder  supports,  bed  plate  and  bearings  of  any  strain. 
The  force  of  the  engine  is  delivered  and  received  in  the 
same  straight  line. 

The  most  difficult  thing  for  an  amateur  to  accomplish  in 
engine  work  is  the  boring  out  of  a  cylinder  casting.  This 
is  a  practical  impossibility  on  a  lathe  having  only  a  slide  rest 
with  hand  feed. 

In  this  design  of  engine  the  cylinder  is  composed  of  a 
drawn  steel  tube,  which  requires  no  boring  out,  as  it  is 
drawn  smooth  on  the  inner  side.  The  piston  shell  is  another 
piece  of  steel  tubing,  which,  being  thinner  and  lighter  than 
a  casting,  reduces  the  weight  of  the  reciprocating  parts  very 
materially. 

Another  very  difficult  piece  of  work  for  the  amateur 
engine  builder  is  the  turning  and  finishing  of  a  crank  shaft. 
This  is  entirely  obviated  by  placing  the  fly  wheels  inside  the 
bearings  and  bed  plate,  and  connecting  them  together  by 
the  crank  pin.  In  this  construction  the  force  exerted  in  the 
cylinder  is  delivered  directly  to  the  fly  wheels  without  first 
passing  through  the  shaft  and  exerting  a  torsional  strain 
therein.  The  only  torsional  strains  on  the  shaft  are  those 
which  drive  the  valve  gearing  on  one  side  of  the  engine, 
and  on  the  other  end  of  the  shaft  the  pulley  placed  there  to 


DESIGN    OF   A   SMALL   GAS   ENGINE. 


43 


44 


GAS   ENGINE   CONSTRUCTION. 


DESIGN   OF   A   SMALL   GAS   ENGINE.  At 

J 

belt  to  the  machine  it  is  desired  to  drive.  This  pulley  is 
not  shown  in  the  cuts  of  the  finished  engine. 

Gas  engines  having  fly  wheels  placed  outside  the  bearings 
require  a  shaft  of  extra  strength,  and  the  fly  wheels  must  be 
very  firmly  keyed  to  the  shaft.  In  this  engine  a  T3F-inch 
round  steel  pin  passing  through  the  hub  of  the  wheel  and 
the  shaft  is  all  that  is  required. 

The  engine  is  of  the  third  class  described  in  the  preceding 
chapter,  one  cylinder,  single  acting,  four-cycle  type. 

The  valve  gearing,  therefore,  which  operates  the  exhaust 
valve,  makes  one  stroke  to  every  two  strokes  of  the  engine. 
This  is  accomplished  by  placing  a  i-inch  gear  wheel  on  the 
engine  shaft  and  a  2-inch  gear  on  the  gear  stud  set  on  the 
main  bearing,  as  shown  in  Fig.  19.  In  the  web  of  this 
gear  wheel  is  placed  a  steel  crank  pin,  to  which  is  attached 
one  end  of  the  connecting  rod,  which  gives  the  necessary 
reciprocating  motion  to  the  valve  rod. 

The  gear  wheels  of  the  valve  gearing  are  set  in  such  a 
position  in  relation  to  each  other  that  the  valve  rod  comes 
in  contact  with  the  lever  of  the  exhaust  valve  and  opens  the 
valve  just  as  the  piston  is  coming  to  rest  at  the  end  of  the 
impulse  stroke,  and  the  valve  closes  just  as  the  piston  starts 
forward  again  on  the  admission  stroke. 

The  inlet  valve  is  entirely  automatic,  opening  when  the 
piston  travels  forward  on  its  admission  stroke,  and  is  closed 
by  the  spring  on  the  end  of  the  valve  stem  when  the  piston 
has  reached  the  end  of  the  forward  stroke. 

Its  action  is  simply  as  an  air-pump  valve,  the  cylinder 
and  piston  being  the  pump  on  the  admission  stroke. 

The  gas  supply  is  graduated  by  the  stopcock,  shown  on 
the  inlet  valve  in  Figs.  19  and  21. 

The  ignition  of  the  charge  is  accomplished  by  an  electric 
spark.  This  is  made  by  the  use  of  an  induction  coil  placed 


46 


GAS   ENGINE   CONSTRUCTION. 


MTT1 


FIG.  21. — END  ELEVATION  OF  FINISHED  ENGINE. 


DESIGN   OF  A   SMALL   GAS   ENGINE.  47 


• 


in  any  convenient  location  near  the  engine.  One  wire  lead- 
ing from  the  battery  to  the  coil  connects  with  the  contact 
springs  pi  ced  behind  the  2-inch  gear  wheel  of  the  valve 
gearing.  These  contacts  are  brought  together,  and  the 
current  passes  through  the  coil  once  in  every  two  revolu- 
tions of  the  engine.  The  contacts  are  pressed  together  by 
a  fiber  pin  placed  in  the  hub  of  the  2-inch  gear  wheel. 

The  igniter  is  placed  in  the  cylinder  head,  just  above  the 
valves.  This  is  shown  in  Fig.  21. 

The  brass  contact  springs  are  seen  in  the  same  cut,  stand- 
ing behind  the  2-inch  gear  wheel.  Two  small  wires  are 
shown  projecting  from  the  screws  on  the  lower  end  of  the 
contacts. 

The  detailed  descriptions  of  these  parts  and  connections 
are  to  be  found  in  Chapter  XX. 

The  governing  of  the  speed  of  the  engine  is  accomplished 
by  an  inertia  governor.  This  is  an  original  design,  is  easy 
to  construct,  and  will  be  found  very  effective  in  operation. 
Detailed  description  and  drawings  will  be  found  in  Chapter 
XIX,  clearly  showing  its  construction  and  operation. 


Chapter  IV. 
PATTERNS. 

PATTERN    WORK.        DRAFT.        GLUE.        FINISH     OF     PATTERNS. 
CYLINDER      COLLAR.        LATHE      WORK.        PISTON 
PATTERN.        PACKING    RING.        CYL- 
INDER   HEAD. 


CHAPTER    IV. 

PATTERNS. 

In  dealing  with  this  work  we  shall  not  go  into  the  subject 

of  complicated  patterns,  with  core  prints  and  core  boxes,  by 

which  means  the  holes  can  be  cast  in  some  of  the  parts  and 

only  need  boring  out  to  finish.     A  study  of  any 

General    good    book   on   pattern-making    will   give   these 

points. 

Our  aim  is  to  show  the  amateur  how  this  work  can  be 
done  in  its  simplest  form. 

The  best  material  to  use  for  those  patterns  which  are  to 
be  turned,  will  be  white  pine.  This  should  be  selected  of 
close  grained  lumber  and  thoroughly  dry.  The  bed  plate 
pattern,  however,  is  best  made  of  mahogany,  which  can  be 
procured  of  any  dealer  in  scroll-sawing  material.  This  wood 
works  very  nicely  also  in  the  patterns  which  have  to  be 
built  up. 

All  patterns  require  draft.  That  is,  they  must  taper 
slightly  in  one  direction,  to  allow  being  removed  from  the 
mould  of  sand. 

This  draft  must  not  be  less  than  one-half  inch  for  every 
foot  in  height  for  a  nice,  smooth  pattern. 

An  allowance  must  also  be  made  for  shrinkage  of  the  metal 
in  casting.  That  is,  the  pattern  for  a  particular  casting 
should  have  about  one-eighth  inch  added  to  it  for  every  foot 
in  length  and  breadth  of  the  finished  size. 


52  GAS   ENGINE   CONSTRUCTION. 

Another  allowance  must  be  made  for  the  metal  necessary 
to  be  removed  in  turning  and  finishing  any  part  of  the 
castings. 

This  will  make  your  patterns  a  little  larger  than  the  fin- 
ished parts. 

Use  the  best  quality  of  glue  in  fastening  the  various  parts 
of  the  patterns  together,  and,  where  possible  without  danger 
of  splitting,  use  also  small  nails  or  screws. 

The  patterns  should  be  smoothed  up  with  fine  sandpaper 
when  finished,  and  all  uneven  places  and  depressions  filled 
with  putty  or  beeswax. 

In  sandpapering  the  patterns,  be  careful  not  to  take  off  the 
corners,  or  otherwise  disfigure  them.  After  they  have 
been  smoothed  up  give  each  one  a  coat  of  shellac  with  a  good 
soft  brush,  and  set  them  aside  to  dry. 

After  they  are  thoroughly  dry,  it  may  be  found  that  on 
those  parts  of  the  patterns  where  the  end  grain  of  the  wood 
is  exposed  they  are  rough.  This  should  be  sandpapered 
down  again,  and  the  pattern  given  another  coat  of  shellac. 
It  will  be  found  advisable  to  give  each  pattern  three  coats 
of  shellac,  rubbing  down  all  unevenness  with  fine  sandpaper. 

When  sandpapering  any  flat  surfaces,  the  sandpaper  can 
be  folded  over  a  small,  flat  block  of  wood,  which  will  pre- 
vent it  from  spoiling  the  surfaces  or  the  sharp  corners  of  the 
patterns. 

We  will  first  take  up  the  pattern  for  the  cylinder  collars. 
These  are  both  cast  from  the  same  pattern. 

It  will  be  noticed,  in  Fig.  22,  that  the  lugs  are  of  different 
shape,  that  on  one  side  being  rounded  on  the 
Cylinder       end,  and  the  other  being  square. 
Collars  I11  making  up  this  pattern  the  collar  can  be 

turned  from  a  piece  of  pine. 

An  excellent  way  to  hold  this  piece  while  turning  is  to 


PATTERNS.  53 

,  0 

fasten  a  piece  of  hard  wood  to  the  face  plate  of  the  lathe  by 
screws  passing  through  from  the  back  of  the  face  plate  into 
the  wood. 

A  tool  having  a  rounded  point  can  then  be  set  in  the  slide 
rest  of  the  lathe  and  the  face  of  the  hardwood  piece  turned 
off  true.  A  piece  of  pine  about  i^  inches  thick,  and  large 
enough  to  be  turned  down  to  the  proper  size,  can  then  be 
glued  to  the  face  of  the  hardwood  block  and  clamped  there 
until  the  glue  hardens.  When  this  is  ready,  the  slide  rest 
should  be  set  at  a  slight  angle  to  turn  down  the  outside  of 
the  pattern,  and  give  it  a  smaller  diameter  toward  the  tail 
stock  of  the  lathe.  This  is  for  draft  in  moulding  the  pattern. 
While  the  irregular  projections  of  the  piece  of  pine  are  being 
turned  down,  it  will  be  advisable  to  place  the  tail  stock 
center  of  the  lathe  against  the  work  to  help  support  it. 

After  the  outside  of  the  pattern  is  turned  to  size,  set  the 
slide  rest  at  a  slight  angle  in  the  opposite  direction  for  turn- 
ing out  the  inside  of  the  pattern,  the  result  being  that  it  will 
have  draft  on  both  the  outside  and  inside  toward  the  tail 
stock  of  the  lathe,  and,  when  moulded,  will  leave  the  sand 
without  destroying  the  mould. 

After  the  piece  has  been  finished  with  fine  sandpaper  while 
revolving  in  the  lathe,  it  is  ready  to  be  cut  away  from  the 
hardwood. 

Set  the  slide  rest  squarely  with  the  lathe  bed,  and  place  a 
cut-off  tool  in  the  slide  rest.  With  this  the  pattern  can  be  cut 
off  the  right  depth,  after  which  the  superfluous  wood  and 
glue  can  be  turned  off  from  the  face  of  the  hardwood  block, 
and  it  will  be  ready  for  a  similar  piece. 

A  piece  of  pine  large  enough  to  make  one  of  the  lugs,  is 
now  placed  in  the  chuck  of  the  lathe  and  turned  down  to  the 
proper  size,  not  omitting  the  draft,  and  a  piece  the  right 
length  cut  off. 


54  GAS   ENGINE   CONSTRUCTION. 

Two  triangular  pieces  of  wood  the  same  height  as  the  lug 
are  now  to  be  whittled  out  with  their  sides  hollowed  to  fit 
against  the  collar  and  the  lug.  The  outer  sides  are  then 
hollowed  to  form  a  fillet  between  the  collar  and  the  lug. 
The  other  lug,  being  square  ended,  is  cut  out  the  proper 
size  and  fitted  to  the  opposite  side  of  the  collar,  after  which 
fillets  are  fitted  on  either  side  of  it. 

The  cut,  from  a  photograph  of  this  pattern,  shows  clearly 


FIG.  22. — PATTERN  FOR  CYLINDER  COLLARS. 

the  mode  of  construction.  In  this  case,  however,  the  collar 
was  turned  from  pieces  of  mahogany  glued  up  with  the  grain 
of  the  alternate  layers  at  right  angles.  This  is  shown  by 
the  dark  and  light  bands  which  surround  this  part  of  the 
pattern. 

After  the  lugs  have  been  fitted,  the  several  parts  can  be 
glued  together. 

In  fitting  these  parts  together,  be  careful  and  get  the  lugs 


PATTERNS.  55 

t  ' 

•diametrically  opposite  each  other.  If  this  is  not  done,  it 
will  look  very  badly  when  the  holes  are  put  through  the  lugs 
for  the  side  rods. 

After  the  glue  is  hard  the  parts  are  finished  and  shellacked, 
as  described. 

All  the  cuts  in  this  chapter  show  the  general  appearance 
of  the  different  patterns.  For  the  actual  dimensions,  the 
reader  is  referred  to  the  detail  drawings  in  the  chapters 
treating  on  the  machine  work  of  the  different  parts. 

The  piston  pattern  is  built  up  from  several  pieces.    These 


FIG.  23. — PISTON  PATTERNS. 

comprise  the  back  or  end  of   the  piston,    the  two  lugs  or 
bosses  which  are  bored  and  reamed  to    fit  the  piston  pin 
and  the  two  standards   which    connect    the    back 
PiStOn    and  bosses. 

The  back  is  formed  of  a  piece  of  wood,  which 
may  be  glued  to  the  hardwood  block  on  the  face  plate. 

In  this  case,  however,   we  must  consider  the  draft  of  the 
pattern  in  another  way. 

On  referring  to  the  cut  of  the  patterns  (Fig.  23)  it  shows 


56  GAS   ENGINE   CONSTRUCTION. 

a  built  up  pattern  of  wood  and,  also,  a  metal  pattern  made  in 
two  parts. 

That  half  of  the  metal  pattern  which  is  lying  flat  repre- 
sents what  the  pattern  would  look  like  when  the  lower  half 
of  it  is  in  one  part  of  the  mould  and  represents  the  direction 
of  the  draft  of  the  upper  part.  From  this  it  will  be  seen 
that  when  the  disc  forming-  the  back  of  the  piston  is  turned 
up  in  the  lathe  the  slide  rest  must  be  set  at  a  slight  angle 
to  make  disc  thinner  on  the  edge  than  in  the  center. 

On  the  back  of  the  piston  pattern  is  a  smaller  disc.  This 
is  what  is  called  a  "  chuck  piece  "  and  is  only  used  to  hold 
the  piston  while  the  casting  is  being  turned  off.  The  jaws 
of  the  chuck  are  gripped  on  this  piece  during  that 
operation,  after  which  the  chuck  piece  is  turned  off,  leaving 
the  back  of  the  piston  flat.  This  can  be  seen  by  referring  to 
Figs.  23  and  56. 

The  back  of  the  piston  and  chuck  piece  can  be  turned 
from  the  same  piece  of  wood,  after  which  they  are  cut  from 
the  hardwood  block  by  a  cutting  off  tool,  or  a  saw  can  be 
used. 

This  piece  can  now  be  held  in  the  jaws  of  the  chuck  by 
the  chuck  piece  and  the  front  faced  off  and  beveled  for  draft. 

The  two  bosses  are  turned  from  a  piece  of  wood  held  in 
the  chuck  and  then  cut  off  the  right  length.  It  will  be  seen 
that  the  inner  ends  of  the  bosses  are  rounded,  to  give  the 
proper  draft. 

The  standards  are  now  built  up  of  pieces  glued  to  the 
back  at  the  lower  end  and  the  bosses  set  on  at  the  other. 
Be  careful  to  get  these  parts  on  a  line  with  the  center  of  the 
back. 

Two  small  braces  are  placed  between  the  standards,  as 
shown,  and  glued  into  place,  after  which  a  small  piece  is 
placed  across  the  tops  of  the  standards.  This  piece  helps  to 


PATTERNS.  57 

t 

keep  the  pattern  in  shape,  and  is  also  a  support  for  the  cast- 
ing when  turning  it  down  to  fit  the  steel  tube  which  forms 
the  piston  shell. 

When  the  glue  is  hard  the  pattern  is  held  in  the  chuck  by 
the  chuck  piece,  and  the  outside  of  the  standards  turned  off. 
This  operation  gives  draft  to  the  outside  of  the  standard, 
and  the  inside  must  be  rounded  up  by  hand. 

This  looks  like  a  difficult  piece  of  work  at  first  sight,  but 


FIG.  24. — PISTON  PACKING  RING. 

if  these  directions  are  followed,  little  trouble  will  be  found 
in  making  it. 

The  piston  packing  ring  is  a  very  simple  piece,  and 
requires  no  explanation.  The  sizes  can  be  had  from  the 
detail  drawings,  and  it  can  be  turned  up  from  a  piece  of 
wood  glued  to  the  hardwood  block  and  cut  off  after 
finishing. 

The  cylinder  head  is  also  a  simple  pattern.  This  requires 
draft  on  the  edge  only.  It  may  be  turned  upon  a  half-inch 
mandrel  or  arbor. 


58  GAS   ENGINE   CONSTRUCTION. 

Drill  a  half-inch  hole  in  the  center  of  a  piece 
large  enough   to  turn  down  for  the  pattern,  and 
finish  as  shown  in  the  cut,  leaving  a  small  pro- 
jection on  one  side  which  is  to  be  turned  to  fit  inside  the 
cylinder  when  the  casting  is  finished. 

After  the  pattern  is  finished   and   sandpapered    smooth, 
drive  out  the  mandrel  and  insert  in  the  half-inch  hole  a  small 


FIG.  25. — CYLINDER  HEAD  PATTERN. 

chuck  piece  projecting  about  three-quarters  of  an  inch  from 
the  face  of  this  pattern.  This  piece  must  be  tapered  slightly 
to  give  it  draft  lengthwise. 

This  chuck  piece  is  to  hold  the  head  while  the  casting  is 
faced  off  on  the  inside  and  the  edge  turned  down  to  size. 

The  cut  shows  the  projection  on  the  inside  face  of  the 
pattern,  and  the  chuck  piece  on  the  outside  face  tilts  the 
pattern  forward. 


Chapter  V. 
PATTERNS— CONTINUED. 

MAIN      BEARINGS.        FILLETS.        CYLINDER     SUPPORTS.        CON- 
NECTING  ROD    HEAD.        PISTON   END    OF 
CONNECTING   ROD. 


CHAPTER    V. 

PATTERNS — CONTINU  ED. 

The  patterns  for  the  main  bearings  are  built  up  from  a 
number  of  pieces,  and  care  is  required  to  get  them  in  proper 
alignment  and  of  equal  dimensions. 

The  draft  is  each  way  from  the  center  band 

Main         which  is  turned  around  the  hub  of  the  bearing. 
Bearings          It  w^l  be  seen  from  the  cuts  and  detail  draw- 
ings that  these  patterns  are  alike,  with  the  ex- 
ception that  they  are  right  and  left  patterns. 

The  only  variation  from  this  being  that  on  the  pattern 
belonging  to  the  valve  gearing  side  of  the  engine  a  small  pro- 
jection is  set  on  the  side  rod  boss  to  support  the  gear  stud. 

The  first  operation  will  be  to  turn  up  the  hubs  or  main 
parts  of  the  bearings. 

A  piece  of  wood  large  enough  to  turn  out  both  hubs 
should  be  placed  in  the  chuck  with  the  outer  end  supported 
by  the  back  center. 

A  round-point  tool  is  best  to  use  for  these  pieces  of  the 
patterns  in  forming  the  ring  around  the  bearing.  Have  the 
slide  rest  set  to  give  the  piece  draft  each  way  from  this 
center  ring,  and  be  sure  that  they  are  both  of  equal  size  and 
shape. 

Next  make  the  bases,  giving  them  draft  sidewise  from  the 
center  on  top,  bottom  and  ends,  and  allowing  for  facing  off 
the  bottom. 


62  GAS   ENGINE   CONSTRUCTION. 

Bore  a  half-inch  hole  through  the  center  of  the  bases,  and 
also  into  the  bearing  hubs,  the  center  of  the  hole  being 
exactly  at  the  center  c5f  the  ring  formed  on  the  boss. 

Turn  out  and  finish  two  wood  pins  one-half  inch  in  diam- 
eter, and  of  sufficient  length  to  form  the  center  of  the 
standard  between  the  base  and  the  bearing. 

Glue  these  pins  into  the  half-inch  holes  bored  in  the  bases 
and  bearings,  and  be  sure  that  the  two  patterns  at  this  stage 
are  exactly  the  same  height.  The  remainder  of  the  standards 


FIG.  26. — PATTERNS  FOR  MAIN  BEARINGS. 

are  formed  by  glueing  on  pieces  of  one-eighth  inch  mahog- 
any on  the  sides  and  one-quarter  inch  pieces  on  the  ends. 
The  half-tones  show  this  construction  plainly.  Next  turn 
out  two  pieces  of  wood  to  form  the  bosses  for  the  side  rods. 

The  only  draft  necessary  to  allow  is  on  the  outer  ends, 
which  should  be  slightly  rounded. 

These  pieces  are  now  to  be  fitted  and  glued  to  the  bear- 
ing, as  shown. 

Great  care  should  be  exercised  to  have  these  bosses 
exactly  parallel  to  the  bases  of  the  patterns,  otherwise 


PATTERNS.  63 

• 

the  bearing  will  have  a  bad  appearance  when  cast  and 
finished. 

For  the  oil  cups,  two  small  projections  are  turned  out  and 
set  on  the  top  of  the  bearings,  and  the  projection  to  support 
the  gear  stud  is  glued  to  the  side  of  the  proper  pattern. 

Around  the  bottom  of  the  standard,  where  it  is  attached 
to  the  base,  a  rounded  .finish  is  made  by  using  a  little  bees- 
wax and  rubbing  it  into  shape  with  a  piece  of  hardwood  or 
metal  having  a  ball-shaped  end  about  •£$  inch  in  diameter. 


FIG.  27. — CYLINDER  SUPPORT  PATTERN. 

This  is  what  is  called  putting  on  a  fillet,  and  should  always 
be  done  in  pattern  work  Avhere  two  surfaces  meet  at,  or 
nearly  at,  a  right  angle. 

The  patterns  are  then  ready  to  be  shellacked  and  finished. 
The  cylinder  supports  are  both   cast  from  one  pattern. 
The  base  and  standard   of  this  pattern  are  con- 
structed  exactly  like  the  main  bearing  patterns, 
Supports      and  the  draft  should  be   made  the  same.     The 


64  GAS   ENGINE   CONSTRUCTION. 

cylindrical  parts,  through  which  the  side  rod  passes,  must 
be  rounded  slightly  on  the  ends  for  draft,  and  in  the  finished 
pattern  the  center  of  this  part  must  be  on  an  exact  line  with 
the  center  of  the  boss  on  the  main  bearing. 

Great  care  should  also  be  taken  to  have  this  part  and  the 
base  parallel. 

The  cut  shows  clearly  the  construction  of  the  pattern. 

The  pattern  for  the  outer  or  crank-pin  end 
Connecting  of  the  connecting  rod  can  be  made  in  either  of 
Rod  Ends     two  ways.     The  half-tone  shows  both  styles 
of  pattern. 


FIG.  28. — PATTERN  OF  OUTER  END  OF  CONNECTING  ROD. 

In  the  wood  pattern,  where  the  whole  head  is  cast  in  one 
piece,  it  is  intended  to  be  cut  apart  with  the  hack-saw  and 
the  two  pieces  fitted  and  screwed  together,  after  which  it  is 
bored  and  reamed  for  the  crank-pin.  In  this  case  the  draft 
would  be  up  and  down,  as  the  pattern  lies  in  the  cut. 

Where  the  pattern  is  made  in  two  parts,  however,  the 
draft  is  upwards  on  both  pieces  and  the  stem  must  be  tapered 
slightly. 


PATTERNS.  65 

To  make  the  solid  pattern  the  center  piece  is  first  turned 
to  size  after  which  it  is  cut  apart  with  a  saw  or  split  with  a 
chisel,  and  after  the  two  halves  are  trued  up  a  piece  of 
linch  mahogany  is  set  in  between  them  and  glued.  The 
stem  is  next  turned  and  fitted  on,  after  which  the  lugs  are  set 
on  through  which  the  screws  pass  to  hold  the  finished 
parts  together.  As  the  pattern  from  which  the  half-tone 
was  made  was  built  up  of  different  colored  woods,  it  is  easy 
to  see  how  the  parts  are  fitted  together,  and  further  explana- 
tion is  unnecessary. 


FIG.  29. — PATTERN  OP  INNER  END  OF 
CONNECTING  ROD. 

In  making  up  the  pattern  in  two  pieces  the  center  piece  is 
first  turned  to  size  and  shape,  after  which  it  is  cut  apart,  but 
in  this  case  it  should  be  cut  just  a  little  to  one  side  of  the 
center.  This  is  to  allow  for  the  facing  off  of  one  of  the 
pieces.  On  the  other  piece  a  thin  strip  of  wood  is  glued  to 
make  up  the  allowance  for  facing  off  that  piece. 

The  stem  is  next  turned  to  shape  and  fitted  on  to  one  of 
the  halves,  and  the  lugs  Lor  the  screws  are  made  and  put  on, 


66  GAS   ENGINE   CONSTRUCTION. 

but  in  this  case  there  will  be  four  pieces  to  fit  instead  of  twor 
and  in  fitting  them  the  two  patterns  should  be  held  together 
to  see  that  these  lugs  correspond  in  their  relative  posi- 
tions. 

The  pattern  for  the  inner  or  piston  pin  end  of  the  con- 
necting rod  is  made  exactly  like  the  one  first  described, 
except  that  it  has  no  lugs  for  screws.  This  piece  when  cast 
is  left  solid  and  is  not  cut  apart  to  give  adjustment  for  wear. 

The  center  or  bearing  is  first  turned  to  shape  and  the 
stem  then  made  and  fitted.  The  pattern  is  moulded  as  it 
lies  in  the  cut  and  the  draft  is,  therefore,  from  the  center  ur> 
and  down. 

The  end  of  the  stem  must  be  rounded  for  this  purpose. 


Chapter  VI. 
PATTERNS— CONCLUDED. 

BED   PLATE.       FLY-WHEELS.       VALVE     ROD    GEARING.       INLET 

VALVE.        EXHAUST     VALVE.        EXHAUST     VALVE 

LEVER.        GOVERNOR.        STARTING 

HANDLE. 


CHAPTER   VI. 

PATTERNS — CONCLUDED. 

The  bed-plate  pattern  is  the  largest  pattern  which  is  to  be 

made;  but,  as  everything  is  in  straight  lines,  we  think  little 

difficulty  will  be  encountered  in  constructing  it.     The  bed 

plate  is  in  reality  a  box  open  at  the  bottom  and 

Bed  Plate      with  a  section  removed  from  the  top  and  one 

end.     The  cut  clearly  shows  the  construction 

of  the  pattern.     The  dimensions  are  all  given  in  the  detail 

drawings. 

The  pattern  is  best  made  of  mahogany.  The  sides  and 
cylinder  end  should  be  one-eighth  inch  thick,  the  top  and 
the  end  which  is  cut  away  for  the  fly-wheels  should  be  one- 
quarter  inch  thick.  Around  the  entire  base,  strips  one- 
quarter  inch  thick  and  one  inch  wide  are  glued  on,  and  on 
each  side  two  pieces  of  mahogany  one-eighth  inch  thick  are 
glued,  to  reinforce  the  pattern  under  the  main  bearings  and 
cylinder  supports.  The  exact  measurements  of  these  pieces 
will  be  found  from  the  detail  drawings. 

At  each  corner  of  the  top,  pieces  of  one-quarter  inch 
mahogany  are  placed,  on  which  the  main  bearings  and 
cylinder  supports  are  to  rest. 

Four  lugs  are  attached  to  the  bottom  of  the  pattern,  by 
which  the  finished  bed  plate  is  screwed  or  bolted  to  the 
foundation. 

The  four  corners  of  the  pattern  should  be  rounded  nicely, 


GAS   ENGINE   CONSTRUCTION. 


FIG.  30. — BED  PLATE  PATTERN  WITH  SUPPORT  IN  POSITION  FOR 

MOULDING. 


FIG.  31. — BED  PLATE  PATTERN  WITH  SUPPORT  REMOVED. 


PATTERNS. 


72  GAS   ENGINE   CONSTRUCTION. 

and  also  the  inner  corners  of  the  reinforcing  pieces  on  each 
side.  On  the  inside,  at  each  of  the  corners,  also  where  the 
top  and  sides  join,  a  fillet  must  be  placed. 

These  can  be  purchased  at  the  machinists'  supply  stores, 
of  leather  cut  in  a  triangular  shape,  which,  when  glued  into 
place,  form  a  nice,  rounded,  smooth  corner.  Strips  of 
straight-grained  wood  can  be  glued  into  the  corners,  and 
then  hollowed  out  with  a  gouge,  if  the  ready-made  fillets 
cannot  be  procured. 

The  slant  of  the  sides  gives  draft  to  the  outside  and  inside 
of  the  pattern,  in  addition  to  adding  to  the  appearance  of 
the  finished  engine. 

In  the  detail  drawing  is  shown  a  casing  for  the  two  fly- 
wheels, which  is  cast  with  the  bed  plate. 

This  can  be  omitted,  if  desired,  and  the  pattern  left  as 
shown  in  the  half-tones.  In  the  latter  case,  a  box  or  support 
must  be  fitted  into  the  bed  plate  to  fill  up  the  cut-away  por- 
tion of  the  pattern,  while  it  is  being  moulded  in  the  position 
shown.  This  support  is  removed  when  the  mould  is  turned 
over,  and  the  sand  is  then  packed  into  the  inside  of  the 
pattern  and  the  other  half  of  the  moulding  flask  filled. 

We  advise  the  use  of  this  open  pattern,  as  it  is  easier 
to  construct,  and  the  castings  come  ou;  in  better  shape. 

If  it  is  desired  to  have  the  lower  part  of  the  wheels 
encased,  a  sheet-metal  casing  can  be  fitted  inside  the  bed 
plate  after  the  fly-wheels  are  in  position. 

The  fly-wheel    pattern    can  be  made  from 
Fly-Whed     one   piece   of  wood,   or   two  or  more  pieces 
may  be  glued  together  with  their  grains  at 
right  angles  for  strength. 

A  hole  can  be  bored  through  the  center  of  the  wood  and 
a  mandrel  driven  through,  on  which  the  pattern  can  be 
turned  up. 


PATTERNS. 


73 


74 


GAS   ENGINE   CONSTRUCTION. 


After  the  pattern  is  turned  to  shape  it  can  be  removed 
irom  the  mandrel  and  the  arms  marked  out,  after  which 
the  wood  is  to  be  cut  away  between  them  and  the  edges 
of  the  arms  rounded. 

One  of  the  arms  of  the  fly-wheel  is  enlarged  a  short  dis- 
tance from  the  hub  and  a  boss  glued  on  which  forms  the 
crank. 

After  the  arms  are  marked  out  and  finished,  a  piece  of 
wood  of  the  size  and  shape   shown  in  the  detail  drawings 
must  be  glued  on  the  pattern  inside  the  rim  as  a  counter- 
weight to  the  crank-pin  and  con- 
necting rod. 

To  make  this  pattern  a  lathe 
having  a  swing  of  14  inches  is 
required.  When  the  builder  of 
the  engine  has  no  lathe  swing- 
ing this  size  the  wheel  can  be 
furnished  complete,  turned  and 
bored,  at  a  nominal  price. 

This  pattern  can  be  carved 
out  from  one  piece  or  built  up 
from  several  pieces. 

The  detail  drawings  indicate 
the  shape  and  size  clearly. 

Two  castings   are  required  for  bearings,  one  on    either 
cylinder  collar.     The  bearing  on  the  front 
ValVC  collar  does  not  require  a  boss  to  attach  the 

Rod  Bearing  governor.  It  is  best,  however,  to  make 
only  one  pattern  and  have  both  pieces  cast 
with  the  boss  on.  If  one  is  spoiled  in  drilling  for  the  gov- 
ernor screw  the  boss  can  be  filed  away  from  it  and  it  can 
then  be  used  as  the  front  bearing,  and  the  second  one  fin- 
ished to  hold  the  governor. 


PIG.  34. — VAT;VE  ROD  BEAR- 
ING PATTERN. 


PATTERNS.  75 

f 

The  cut  shows  the  pattern  as  originally  made,  but  the 
reader  will  find  the  detail  drawings  of  this  piece  modified 
to  fit  the  governor. 

Three  patterns  are  required  for  the  inlet  valve.  The  valve 
body  is   turned   up  of   a   single  piece   of  pine  and  is  given 
draft  for  its  entire  length.     It  is  moulded  in  the  position 
shown  in  Fig.  35,  and  should,  therefore,  be  made 
with  the  slide  rest  set  at  a  slight  angle. 

The  projection  at  the  top  of  the  pattern  is  left 
for  a  chuck  piece,  by  which  the  casting  is  held  in 
the   jaws   of  the  chuck,  while   the  outside   and  inside  are 


FIG.  35. — INLET  VALVE  PATTERNS. 

turned,  bored  and  finished,  after  which  it  is  turned  down  to 
a  small  hub  to  act  as  a  bearing  for  the  guide  pin,  as  shown 
in  the  detail  drawings. 

The  valve  pattern  is  best   made   by   building   it  up,   as 
shown  in  the  cut.     It  is  moulded  in  the  position  shown. 

The  valve  disk  of  this  pattern  was  turned  from  a  piece  of 

-J  inch   mahogany.     A  hole  was  drilled  through  the   piece 

Jinch  in  diameter  and  a  mandrel  driven  into  it.  After  it  was 


76  GAS   ENGINE   CONSTRUCTION. 

turned  down  to  size,  the  mandrel  was  removed  and  a  small 
hub  of  pine  turned  down  to  a  diameter  of  T5¥  inch  to  form  a 
hub  for  the  valve  stem,  but  the  end  was  turned  down  to 
1  inch  »to  fit  the  hole  in  the  valve  disk.  After  this  hub  was  cut 
off  it  was  glued  in  place.  The  four  wings  were  made  of 
J-inch  mahogany,  and  after  tapering  them  for  draft,  they 
were  glued  into  position. 

A  fillet  of  wax  is  required  where  the  wings  and  the  valve 
disk  join. 

The  gas  ring,  which,  when  finished,  forms  an  annular  gas 
space  around  the  inlet  valve,  was  moulded  from  the  pattern 
shown  in  the  right  of  the  cut.  It  was  found,  however,  after 
the  ring  was  completed  and  put  in  place,  that  connecting  the 
stop  cock  and  piping  to  the  ring  had  a  tendency  to  loosen  it 
on  the  inlet  valve.  To  overcome  this,  the  lugs  shown  in  the 
detail  drawings,  Fig.  108,  were  added. 

Through  these  lugs  screws  are  to  be  inserted  to  fasten  the 
ring  to  the  cylinder  head. 

The  main  parts  of  the  ring  and  stem  are  clearly  shown  in 
the  cut. 

After  the  round  disk  forming  the  ring  has  been  turned  up 
in  the  lathe  and  cut  off  the  proper  length,  a  hole  of  the 
diameter  of  the  stem  is  bored  in  one  side  and  the  stem 
glued  in.  The  lugs  are  next  glued  around  the  bottom  of 
the  ring,  as  shown  in  the  detail  drawings. 

In  Fig.  36  is  shown  two  patterns  of  the  exhaust  valve  cas- 
ing.    The  wood  pattern  is  shown  in  nearly  the  position  in 
which  it  is  to  be  moulded,  and  the  draft  of  the  parts  must 
be  made  to  conform  to  this.   The  different  grain- 
ExhciUSt      ings   of   the   parts   of   the    wood   pattern  show 
ValVC         clearly  its  construction. 

The  body  of  the  valve  should  be  turned  first. 
It  will  be  noticed  on  inspection  of  the  metal  pattern  in  the 


PATTERNS. 


77 


cut  that  the  lower  portion  below  the  irregular  shaped  flange 
is  slightly  larger  than  the  main  part  of  the  body. 

In  turning  this  piece  into  shape,  a  square  shoulder  is  left, 
and  after  the  irregular  flange  is  bored  to  fit  the  body  of  the 
valve,  it  is  slid  down  against  the  shoulder  and  glued  there. 

The  shape  of  the  flange  is  shown  in  the  detail  drawings. 

From  the  side  of  the  valve  body  an  arm  extends  out,  ter- 


FIG.  36. — EXHAUST  VALVE  PATTERNS. 

minating  in  a  boss,  which  forms  a  bearing  for  the  exhaust 
lever  pin. 

As  will  be  seen,  there  is  an  offset  in  this  arm  to  bring  the 
top  of  the  boss  in  line  with  the  center  of  the  valve  body. 

A  rib  is  attached  to  the  lower  side  of  the  arm  to  strengthen 
it,  as  shown. 

A  boss,  shown  in  the  detail  drawings,  Fig.  113,  is  fitted 
and  glued  to  the  upper  side  of  the  valve  body  for  the 
exhaust  pipe. 


78  GAS   ENGINE   CONSTRUCTION. 

The  projection  on  the  end  of  the  pattern  of  the  body  is 
for  a  chuck  piece  by  which  the  valve  body  is  held  in  the 
chuck  while  being  bored  and  finished.  This  piece  is  after- 
ward cut  away  and  does  not,  therefore,  appear  on  the  detail 
drawings  of  the  finished  valve. 

The  valve  pattern  is  made  up  exactly  like  the  inlet 
valve,  except  that  it  is  very  little  smaller,  as  shown  in 
the  drawings. 

ExhaUSt  The  pattern   of  the  exhaust  valve  lever 

ValVC  LCVer       is  so  simple  that  a   special   cut  of  the  pat- 
tern will  not  be  necessary. 

The  detail  drawings  of  this  piece,  Fig.  115,  will  show  its 
construction  clearly. 

The  governor  patterns  are  very  simple,  and 
Governor       only  two  will  be  required,  the  governor  lever 
and  the  weight. 

The  lever  is  shown  in  the  detail  drawings  in  Fig.  124. 

The  weight  is  a  round  piece  and  can  be  turned  from 
a  piece  of  brass  rod  of  the  size  shown  in  the  drawings. 

The  parallel  pieces  of  brass  which  hold  the  steel  roller  are 
best  made  from  sawed  brass. 

If  this  cannot  be  procured,  however,  they  may  be  cast 
from  a  pattern. 

Starting"          The  pattern  for  the  starting  handle  will  be  a 
Handle       single   piece.     The  details   of   this   pattern  are 
shown  in  Fig.  131  of  the  detail  drawings. 

A  pattern  can  be  made  for  this  piece  or  it 

Piston 

may  be  turned   from   a   piece  of   soud  rod. 

Lubricator     The  .details  are  shown  in  Fig.  47. 

These  directions  will  enable  the  amateur  to  construct 
any  patterns  required  for  this  work,  provided  they  have 
the  necessary  tools ;  if,  however,  they  find  their  facili- 
ties are  not  adequate,  it  will  be  found  much  cheaper  to- 


PATTERNS.  7^ 

procure  a  set   of  the  complete   castings   than  to   have  the 
pattern  made  especially  for  one  engine. 

Fig  37  shows  the  pattern  of  the  angle  plate. 
AnglC         It  is  moulded  in  the  position  shown,  and  the  slots 
Plate       in  tne  back  are  made  a  trifle  wider  at  the  upper 
side,  as  the  pattern  lies  in  this  position,  thus  giving 


FIG.  37. — ANGLE  PLATE  PATTERN. 

the    necessary  draft   to   enable  it  to   be  removed  from  the 
mould. 

The  shelf  of  the  angle  plate  is  also  made  with  a  slight 
draft  toward  the  front. 


80  GAS   ENGINE   CONSTRUCTION. 

The  two  small  brackets  placed  under  the  shelf  give  it 
strength  and  rigidity. 

Dimensions  of  the  different  parts  will  be  found  in  the 
detail  drawings  in  the  chapter  following  this. 


Chapter  VII. 
SPECIAL    TOOLS. 


ANGLE    PLATE.       PIN.      WASHERS.       BUSHINGS.       COLLAR. 
PATTERN.      TURNING    TOOLS    FOR    FLY-WHEELS. 
BORING     TOOLS.        CUTTERS.        CENTER- 
ING   TOOLS. 


CHAPTER     VII. 

SPECIAL   TOOLS. 

In  this  chapter  we  shall  describe  a  few  tools  and  appli- 
ances which  will  be  found  of  great  advantage  to  the  ama- 
teur mechanic.  Most  of  these  can  be  made  very  readily. 

The  angle  plate  is  a  very  important  adjunct  to  the  lathe, 
with  which  most  amateurs  are  not  familiar.  With  a  correct 
angle  plate  fitted  to  the  lathe,  irregular  pieces  may  be  firmly 
and  accurately  held  and  finished. 

To  insure  good  work,  the  back  of  the  angle  plate,  which 
fits  against  the  face  plate  of  the  lathe,  and  the  top  of  the 
horizontal  shelf  must  be  planed  up  at  right  angles  to  each 
other. 

The  face  of  the  angle  plate,  also  the  front  and  bottom  of 
the  horizontal  shelf,  may  be  planed  up,  but  these  are  not  so 
essential. 

In  the  drawing,  Fig.  38,  is  shown  the  angle  plate  attached 
to  the  face  plate  of  the  lathe  and  one  of  the  cylinder  sup- 
ports clamped  in  position  for  facing  off  the  bottom. 

Two  long  slots  are  cast  in  the  back  of  the  angle  plate, 
through  which  are  inserted  the  two  bolts  for  clamping  the 
angle  plate  to  the  face  plate  of  the  lathe. 

The  two  slots  in  the  face  plate,  at  right  angles  to  the  slots 
in  the  angle  plate,  give  a  large  range  of  adjustment  in  bring- 
ing work  of  different  heights  in  line  with  the  lathe  centers. 

Figs.  57,  59,  and  60  best  show  the  angle  plate  in  position. 


84 


GAS   ENGINE   CONSTRUCTION. 


In  the  construction  of  this  engine  the  angle  plate  is  fitted 
with  a  soft  steel  pin  J  inch  in  diameter,  having  a  head  f-inch 
diameter  at  one  end  and  a  hole  i-inch  diameter  drilled  and 
tapped  in  the  opposite  end. 

A  i-inch  hole  should  be  drilled  and  reamed  in  the  shelf 
of  the  angle  plate  at  the  position  shown  in  the  detailed 
drawings. 

The  pin  should  fit  snugly  in  this  hole  to  prevent  it  from 


FACE   F!  ATE 


FIG.  38. — ANGLE  PLATE  AND  FACE  PLATE. 

falling   out    when    the    work   is   being    placed   in   position. 

A  large  washer,  with  a  J-inch  hole  in  the  center,  should  be 
made  by  which  the  work  is  clamped  on  the  steel  pin.  This 
is  shown  in  Fig.  38. 

A  collar  made  from  a  piece  of  heavy  brass  tubing  of  the 
dimensions  shown  in  Fig.  39  will  be  found  of  great  assist- 
ance in  this  work.  Its  use  is  shown  in  Fig.  107. 

Two  small  washers  must  also  be  prepared  to  form  bush- 
ings for  the  angle  plate  pin  when  it  is  desired  to  mount  the 


SPECIAL  TOOLS. 


main  bearings,  connecting  rod  head,  etc.,  on  the  angle  plate. 

These  can  be  made  from  common  f-inch  iron  washers  or 

1  turned  from  a  piece  of  brass  rod.     They  should   be  held  in 


FRONT  VIEW 


SIDE  VIEW 


TAP  /£  -20  THR. 


FIG.  39. — ANGLE  PLATE, 

the  chuck  and  bored  out  to  £-inch  inside  diameter,  after 
which  they  can  be  driven  on  a  mandrel  and  the  outside 
turned  down  to  f-inch  in  diameter  to  fit  the  bore  of  the  main 
bearings,  etc. 


86 


GAS   ENGINE   CONSTRUCTION. 


The  holes  drilled  and  tapped  in  the  shelf  of  the  angle  plate 
are  used  to  clamp  work  which  the  steel  pin  will  not  hold. 
They  can  be  placed  wherever  convenient  and  should  all  be 
drilled  and  tapped  for  the  same  size  of  screw. 

If  it  is  intended  to  turn  the  fly-wheels,  it  is  absolutely  nec- 
essary to  have  the  holes  for  the  crank  pin  bored  at  exactly 
the  same  distance  from  the  holes  for  the  shaft. 

This  is  best  accomplished  as  shown  in  Fig.  40.     A  hole  is 


FIG.  40. — FACE  PLATE  AND  PIN. 

drilled  in  the  face  plate  of  the  lathe  exactly  2  inches  from 
the  center  line  of  the  lathe  spindle.  A  pin  of  steel  is  turned 
to  f  inch  diameter  to  fit  the  bore  of  the  fly-wheel,  and  one- 
end  is  then  turned  down  to  fit  the  hole  drilled  in  the  face 
plate. 

After  both  wheels  have  been  turned  and  bored,  they  are 
separately  mounted  on  this  pin,  the  holes  for  the  crank  pin 
are  then  bored  and  reamed. 

This  is  fully  described  in  the  chapter  on  the  fly-wheels. 


SPECIAL  TOOLS.  f  8/ 

For  turning  and  facing  the  rims  of  the  fly-wheels,  a  tool 
shown  in  Fig.  41  will  be  found  to  answer  admirably.  This 
is  a  piece  of  tool  steel  of  the  size  to  fit  the  tool  post  of  the 
lathe,  bent  into  the  form  shown. 

With  this  tool  the  rim  and  also  the  face  of  the  wheel  next 


FIG.  41. — Tooi,  FOR  TURNING  FLY  WHEEL. 

the  face  plate  can  be  turned  while  the  wheel  is  mounted  on 
the  face  plate  for  boring. 

A  very  convenient  boring  tool  and  one  easily  made  by 


'/4    CENTERING  TOOL    y 

MAKE  ALL  THREE  SAME    LENGTH 


FIG.  42. — BORING  TOOL. 

anyone  is  shown  in  Fig.  42.  This  shows  a  piece  of  machine 
steel  or  iron  of  a  size  to  fit  the  tool  post  of  the  lathe.  A 
hole  is  drilled  at  the  outer  end  from  the  top  and  tapped  for 
a  J-inch  screw. 


88  GAS   ENGINE   CONSTRUCTION. 

Just  back  of  the  tapped  hole  and  at  right  angles  to  it  is 
drilled  and  reamed  a  J-inch  hole  for  the  boring  tools.  A 
short  distance  back  of  this  hole  is  drilled  a  smaller  one.  A 
hack  saw  is  now  used  to  split  the  tool  holder  from  the  end 
to  the  small  hole  back  of  the  boring  tool.  The  upper  part 


FIG.  43. — CENTERING  TOOL. 

of  the  hole  tapped  for  a  screw  is  now  drilled  out  to  ^-inch 
to  form  a  clearance  hole  and  a  screw  fitted  to  clamp  the  tool 
in  position.  The  screw  can  be  made  with  a  head,  as  shown 
in  the  cut,  or  an  ordinary  screw  can  be  used  with  a  slot- 
ted head. 

Various  cutters  made  from  J-inch  drill  rod,  can  be  fitted 
to  this  holder,  and  the  cutting  ends  formed  for  any  pur- 
pose desired. 

In  the  cut  a  smaller  boring  tool  is  shown  removed  from 
the  holder. 


SPECIAL    TOOLS.  89 

Another  very  necessary  tool  for  this  work  is  a  centering 
tool.  This  can  be  made  from  a  piece  of  i-inch  drill  rod  and 
fitted  to  the  boring  tool  holder  or  can  be  a  separate  tool,  as 
shown  in  Fig.  43.  This  consists  of  a  piece  of  tool  steel  to  fit 
the  tool  post  of  the  lathe,  one  end  of  which  is  drawn  out  to 
a  small  point  and  sharpened,  as  shown.  After  being  drawn 
out,  the  tool  is  given  a  bend,  as  shown  in  the  cut. 

The  centering  tool  for  the  boring  tool  holder  is  made  by 
filing  a  piece  of  i-inch  steel  rod  to  a  point  of  about  60°  while 
it  is  revolving  in  the  lathe,  after  which  it  is  filed  on  three 
sides  to  form  a  triangular  pyramid. 

In  Fig.  42  is  shown  the  construction  of  the  point. 


Chapter   VIII. 
CYLINDER. 

WATER    JACKET   SHELL.      MANDREL.      SQUARING   UP   ENDS   OF 

TUBES.         STEEL     CYLINDER     TUBE.         LOCATION     OF 

LUBRICATOR.         CYLINDER      COLLARS*.        JIG 

FOR     LOCATING     HOLES     IN     LUGS. 

THE  JIG   IN   USE.       WATER 

SUPPLY   PIPES. 


CHAPTER  VIII. 

CYLINDER,    ETC. 

It  is  advisable  to  begin  operations  with  the  cylinder  and 
water  jacket. 

The  brass  tube  forming  the  water  jacket  shell  must  be 
faced  off  perfectly  true  at  each  end,  as  on  this  depends  the 
accurate  spacing  of  the  cylinder  collars  and  consequently 
the  alignment  of  the  cylinder. 

As  an  arbor,  or  mandrel,  a  piece  of  hard  wood  may  be 
used.  The  mandrel  shown  in  Fig.  44  was  a  piece  of  maple 


• 

i 


FIG.  44. — TUBING  FOR  WATER  JACKET,  CYLINDER  AND 
PISTON  SHELL,  WITH  HARD  WOOD  MANDREL. 


94 


GAS   ENGINE   CONSTRUCTION. 


1 1 


1^ 
tf) 


CYLINDER,  ETC. 


95 


stove  wood.     This  was  mounted  between  the  centers  of  the 
lathe  and  driven  by  a  bolt  which  passed  through  one  of  the 
slots  of  the  face  plate  and  fitted  into  a  groove  chiseled  into 
the  wood.     The    cut   shows  the 
arrangement  clearly. 

Set  the  slide  rest  and  turn 
down  the  wooden  mandrel  until 
the  brass  tube  can  be  forced  on 
by  hand.  When  the  tube  is  in 
position  on  the  mandrel  face  up 
each  end,  using  a  right  and  left 
side  tool  in  the  tool  post  alter- 
nately. 

Take  light  cuts,  else  the  tube 
may  move  on  the  mandrel.  The 
length  of  the  finished  piece  should 
be  3J-  inches,  as  shown  in  Fig.  45. 

Set  a  round  nose  tool  in  the 
tool  post  and  take  a  cut  across 
the  outside  of  the  tube  to  true  it 
up  with  the  inside,  after  which  it 
may  be  filed  up  smooth  and  pol- 
ished with  emery  cloth  or,  better 
still,  fine  sand  paper. 

Remove  the  jacket  tube  and 
turn  down  the  mandrel  again 
until  the  steel  cylinder  tube  can 
be  forced  on.  Face  up  both  ends 
using  the  side  tools  as  before. 

On  the  end  of  the  cylinder  tube,  which  is  to  be  next  the 
cylinder  head,  turn  down  the  outside  of  the  tube  for  a  dis- 
tance of  -J  inch. 

Leave  a   space  of  3^  inches  full  size  and  turn   down  the 


90  GAS   ENGINE   CONSTRUCTION. 

remainder,  or  front  end,  of  the  tube  to  the  same  diameter  as 
the^  inch  on  back  of  tube,  as  shown  in  Fig.  46.  This  leaves 
the  outside  ends  of  the  cylinder  tube  true  with  the  inside, 
and  when  the  cylinder  collars  are  bored  out  to  fit  onto  the 
ends  of  the  shell  the  cylinder  will  be  in  line. 

Fig.  44  shows  the  cylinder  tube  after  the  ends  have  been 
turned  down  to  size. 

On  the  front  of  the  cylinder,  at  the  position  shown  in  Fig. 


FIG.  47. — LUBRICATOR  FOR  CYLINDER. 

46,  a  hole  is  drilled  for  the  lubricator  which   supplies  oil  to 
the  piston  and  piston  pin. 

The  cylinder  collars  are  chucked  as  shown  in  Fig.  48.* 
Should  the  outside  of  the  casting  not  run  true  when  the 
jaws  of  the  chuck  are  closed  on  it  the  jaws  may  be  loosened 

*The  two  photos  for  Figs.  48  and  50  were  spoiled  and  a  finished 
collar  was  removed  from  the  engine  to  make  the  cuts  shown.  The 
holes  for  side  rods  and  cylinder  head  screws  are  to  be  seen. 


CYLINDER,  ETC. 


97 


t? 
o 


I 

fl 

-*  z 

S  8 
so  w 

<__,  jo 
-  P 

s  ° 
'£ 


•I 

o 


95 


GAS   ENGINE   CONSTRUCTION. 


and  a  piece  of  paper  or  cardboard  placed  under  one  or 
two  of  them  to  obviate  it.  Do  not  place  the  casting  against 
the  jaws  of  the  chuck  on  the  back,  but  leave  about  -J-inch 
space  between  for  clearance  for  the  point  of  the  tool  when 
boring  out  to  fit  cylinder  tube.  A  small  round  point  tool 
can  be  used  to  bore  out  the  casting  to  fit  the  cylinder  tub& 


FIG.  49. — CYLINDER  COLLAR. 

and  also  to  fit  the  brass  jacket  tube  ;  but,  in  the  latter  caser 
a  sharp  point  tool  must  be  used  afterwards  to  cut  out  the 
square  corners. 

The  exact  dimensions  will  be  seen  in  Fig.  49.  Both  tubes 
should  be  a  very  snug  fit  in  the  collar. 

After  the  casting  is  bored  to  fit  the  tubes,  and  while  still 
in  position  in  the  chuck,  face  off  the  edge  of  the  casting. 
The  lugs  on  the  side  of  the  casting  need  not  be  faced  on. 


CYLINDER,  ETC. 


99 


IOO 


GAS   ENGINE   CONSTRUCTION 


this    side,  but   must   be    on    the    opposite    side  in  the    next 
operation. 

After  finishing  the  castings  as  described  remove  them  from 
the  chuck  and  replace  again  with  the  faced  edge  against  the 
chuck  jaws.  Face  up  the  side  of  the  casting  and  the  lugs, 
as  shown  in  Fig.  50.  The  small  round  point  tool  is  best 
adapted  for  this  work.  In  facing  across  the  lugs  very  light 
cuts  should  be  taken  to  prevent  the  casting  from  jarring 
loose  in  the  chuck  jaws. 


FIG.  51. — JIG  FOR  HOLES  ix  CYLINDER  COLLAR  LUGS. 

A  special  jig  must  now  be  prepared  to  locate  the  holes  in 
the  lugs  of  the  cylinder  collars. 

This  is  shown  in  Fig.  51,  in  which  b  is  a  piece  of  flat  steel 
or  iron  J-  inch  by  -J-  inch  and  6  inches  in  length.  Any  con- 
venient width  or  thickness  of  metal  will  do. 

Mark  with  a  scriber  a  line  through  the  center  from  d  to  c, 
and  on  this  line,  midway  between  the  two  ends,  centerpunch 
the  point  c.  With  the  dividers  lay  off  from  this  point  the 
points  f  and  g  2-J  inches  distant,  as  shown.  Drill  a  small 
hole  at  each  of  the  three  points  with  about  a  No.  42  drill. 


CYLINDER,  ETC. 


101 


O 


>  «• 


102  GAS   ENGINE   CONSTRUCTION. 

The  piece  a  is  cast  with  a  small  chuck  piece  on  the  back, 
by  which  it  is  held  in  the  chuck  jaws  while  being  turned 
down  to  size. 

Place  this  casting  in  the  chuck  and  turn  down  the  edge 
until  it  will  just  fit  into  the  cylinder  collar.  Face  off  the 
front  and,  while  it  is  revolving  in  the  chuck,  with  a  sharp 
pointed  hand  tool  or  the  centering  tool  shown  in  Fig.  43, 
make  an  indentation  in  the  center. 

Remove  from  the  chuck  and  drill  a  hole  at  the  indentation 
with  the  same  size  drill  used  at  c. 

A  pin  made  of  wire  the  same  size  as  the  drill  used  can  now 
be  placed  through  the  two  parts  a  and  b  to  hold  them  in 
position  while  two  screws  are  inserted,  as  shown  in  the  cut, 
to  fasten  them  permanently. 

In  using  the  jig,  place  the  round  piece  a  in  the  hole  bored 
in  the  cylinder  collar,  with  the  holes /and  g  in  the  center  of 
the  lugs.  Clamp  in  position  and  drill  the  lugs,  through  the 
holes  /  and  g,  with  the  same  size  drill  as  before. 

Fig.  52  shows  the  jig  in  use.  It  is  best,  in  using  this  jig 
to  have  a  good  large  drill  pad  fitted  to  the  tail  stock  of  the 
lathe  and  the  faced  off  part  of  the  cylinder  collar  held  firmly 
against  the  pad  to  insure  the  hole  .passing  through  straight. 
In  the  cut  shown  the  tail  stock  bears  against  the  back  of  the 
lug  on  the  cylinder  collar.  After  both  lugs  have  been  drilled 
remove  the  jig  and  drill  the  lugs  with  a  -J-inch  drill,  which 
will  follow  the  holes  made  by  the  small  drill. 

Before  the  cylinder  parts  are  put  together  two  holes  must 
be  drilled  and  tapped  in  the  brass  jacket  tube  for  a  J-inch 
pipe,  as  shown  in  Fig.  45.  The  water  is  to  enter  at  the  bot- 
tom and  flow  out  at  the  top  of  the  jacket,  thus  keeping  it  full. 

To  assemble  the  cylinder  parts  it  will  be  necessary  to  have 
the  side  rods  completed,  the  details  of  which  are  to  be  found 
in  another  chapter. 


Chapter  IX. 
PISTON. 

THE    CASTING.       STEEL    SHELL.       TURNING    PISTON    CASTING, 
CUTTING    OFF    THE    CHUCK    PIECE.       FACING    UP    THE 
BACK.        DRILLING,   BORING    AND    REAMING    FOR 
PISTON  PIN.     PISTON  PIN.     FASTENING  PIS- 
TON   SHELL.        LUBRICATING    TUBE 
FOR    PISTON    PIN.       PACKING 
RING. 


CHAPTER     IX. 


PISTON. 


The  piston  is  formed  of  an  outer  shell  of  steel  tubing  and 
a  casting  which  forms  the  head  and  the  wrist  pin  bearing. 
The  shell  must  be  squared  up  at  each  end,  which  can  be 


FIG.   53. — FACING  UP  ENDS  OF  STEEL  PISTON  SHELL. 

done  on  the  wood  arbor  on  which  the  cylinder  tube  was 
turned.  Fig.  53  shows  the  shell  on  the  wood  mandrel  and  a 
side  tool  in  the  tool  post  of  the  lathe  to  square  up  the  end. 


io6 


GAS   ENGINE   CONSTRUCTION. 


PISTON.  ID/ 

t 

The  length  of  the  piston  shell,  when  squared  up,  should 
be  3T7¥  inches. 

The  next  operation  will  be  to  properly  set  the  piston  cast- 
ing in  the  lathe.  A  chuck  piece  is  cast  on  the  back  which  is 
gripped  in  the  jaws  of  the  chuck.  When  the  casting  is  in 
the  chuck,  the  two  bosses  cast  on  the  front  through  which 
the  piston  pin  is  to  pass  should  be  on  a  line  with  the  center 
of  the  lathe. 

When  they  are  brought  to  this  position  the  centering  tool 
should  be  used  to  mark  on  the  distance  piece  cast  on  the 
front  of  the  bosses  a  center,  which  can  be  drilled  by  using  a 
chuck  in  the  tail  stock,  and  into  which  the  tail  stock  center 
is  afterwards  placed  to  support  the  casting  while  it  is  being 
turned. 

Fig.  55  shows  the  casting  held  in  the  chuck  with  the  tail- 
stock  center  in  place  and  a  cut  being  taken  across  the  sides. 
The  casting  should  be  turned  down  until  the  shell  can  be 
placed  on  tight.  A  small  shoulder  is  left  on  the  back  to  act 
as  a  stop  for  the  shell,  but  its  diameter  must  not  exceed  the 
outside  diameter  of  the  shell. 

When  the  casting  has  been  turned  to  the  proper  size, 
remove  it  from  the  chuck,  and  after  the  shell  has  been  placed 
on  the  casting  it  is  inserted  in  the  chuck,  as  shown  in  Fig. 
56.  The  chuck  jaws  are  inserted  into  the  end  of  the  tube 
and  expanded  by  turning  the  chuck  wrench  backward. 
When  the  shell  runs  true  in  the  lathe  an  indentation  may  be 
marked  in  the  end  of  the  casting  and  drilled  for  a  center, 
into  which  the  tail  stock  center  is  placed  to  support  the  end 
while  being  turned. 

Fig.  56  shows  the  piston  and  shell  in  the  lathe  with  a  tool 
in  the  slide  rest. 

The  back  of  the  piston  must  now  be  faced  up  true  and  the 
-chuck  piece  cut  off. 


io8 


GAS   ENGINE   CONSTRUCTION. 


O 

I 

0 


PISTON. 


IC9 


no 


GAS   ENGINE   CONSTRUCTION. 


Remove  the  parts  from  the  lathe  and  separate  the  shell 
and  piston  casting. 

The  casting  is  to  be  mounted  on  the  angle  plate,  as  shown 
in  Fig.  57,  to  be  drilled,  bored,  and  reamed  for  the  piston 
pin. 

It  must  be  set  at  the  proper  height  to  drill  the  hole 
through  the  center  of  the  two  piston  pin  bosses,  and  the 


FIG.  57. — DRILLING  PISTON  CASTING  FOR  PISTON  PIN. 

bosses  must  be  squared  up  by  using  a  straight  edge  to  true 
them  up  with  the  lathe  bed,  or  a  steel  square  can  be  used  to 
square  them  up  by  the  back  of  the  angle  plate. 

Fig.  57  shows  clearly  the  method  of  clamping  the  casting 
on  the  angle  plate. 

When  lined  up  and  in  the  proper  position,  start  the  lathe, 
and  with  the  centering  tool  mark  an  indentation  at  the  cen- 


PISTON. 


Ill 


ter  of  revolution  of  the  casting.  Start  a  T\-inch  drill  at  this 
indentation  with  the  end  of  the  drill  against  the  back  center, 
Fig.  57  shows  the  drill  started  and  a  clamp  used  to  keep  the 
drill  from  revolving.  The  clamp  is  held  in  the  left  hand 


FIG.  58.— PISTON. 

while  the  drill  is  fed  by  the  right  hand  turning  the  tail  stock: 
screw. 

When  the  drill  has  cut  through  the  first  boss  of  the  cast- 
ing, a  boring  tool  can  be  placed  in  the  tool  post  and  the  hole 
bored  out  to  fit  the  end  of  a  -|-inch  reamer.  Pass  the  reamer 
through  the  hole  with  the  lathe  running  at  its  slowest  speed. 


112 


GAS   ENGINE   CONSTRUCTION. 


PISTON. 


114  GAS   ENGINE   CONSTRUCTION. 


ig-  59  shows  the  reamer  in  position  and  prevented  from 
turning  by  the  small  wrench.  The  boring  tool  is  still  in  the 
tool  post. 

The  hole  in  the  second  boss  must  now  be  drilled.  Start 
the  drill  in  the  center  by  passing  it  through  the  finished 
hole  in  the  front  boss,  then  bore  and  ream  as  before. 

Fig.  60  shows  the  boring  tool  extended  to  reach  the  back 
boss. 

The  casting  can  now  be  removed  from  the  lathe  and  the 
distance  piece  cut  off  even  with  the  end  of  the  bosses. 


MACHINE  STEEL 

MAKE  ONE 


FIG.  61. — PISTON  PIN. 

Through  the  holes  in  the  two  bosses,  fit  a  piece  of  ^-inch 
steel  rod,  the  ends  of  which  must  not  project  on  the  outside 
surface  and  interfere  with  placing  in  position  the  piston 
shell. 

In  Fig.  72  is  shown  the  piston  casting  with  the  piston 
pin  fitted. 

Drill  through  one  of  the  bosses  and  the  piston  pin  and 
insert  a  small  pin  to  prevent  the  piston  pin  from  rotating  in 
the  holes. 

Place  the  shell  in  position  and  insert  two  No.  4  flat-head 
machine  screws  through  the  shell  on  opposite  sides  and 
screwed  into  the  piston  casting  to  hold  the  shell  in  place. 

Be  sure  that  the  screw  holes  in  the  shell  are  countersunk 


PISTON.  115 

9 

deep  enough  so  that  there  will  be  no    danger  of  the  screw 
heads  rubbing  on  the  inside  of  the  cylinder. 

A  small  hole  should  be  drilled  in  the  top  of  the  piston 
shell  directly  over  the  center  of  the  piston  pin  and  a  small 
piece  of  brass  tubing  driven  down  into  it,  which  almost 
reaches  the  oil  hole  in  the  connecting  rod  end.  This  hole 


A  , CLEARANCE  HOLE 

FOR*  6-32  SCR. 


CAST  IRON 

MAKE  ONE 


FIG.  62. — PISTON  PACKING  RING. 

will  be  seen  in  the  detail  drawing  of  the  piston  shell.  The 
tube  receives  oil  from  the  lubricator  on  the  end  of  the  cylin- 
der as  it  passes  beneath  and  delivers  it  to  the  piston  pin. 

When  the  connecting  rod  is  finished  the  shell  must  be 
removed  and  the  piston  pin  unpinned  and  slid  out  sufficiently 
to  allow  of  placing  the  connecting  rod  on  the  pin.  The  pis- 
ton parts  are  then  placed  together  as  before. 

To  make  a  tight  fit,  without  an  excess  of  friction,  a  pack- 
ing ring  is  introduced  into  the  cylinder  and  screwed  to  the 
back  of  the  piston. 


u6 


GAS   ENGINE   CONSTRUCTION. 


This  ring  and  the  back  of  the  piston  form  a  V-shaped 
groove,  into  which  a  packing  of  asbestos  is  placed.  The 
shape  of  the  groove  causes  the  asbestos  to  press  against  the 
inside  of  the  cylinder  when  the  screws  fastening  the  ring 
and  piston  together  are  tightened. 

The  ring  is  held  in  the  chuck  jaws,  as  shown  in  Fig.  63, 
while  the  face,  front,  shoulder,  and  bevel  face  are  finished 


FIG.  63. — FINISHING  INSIDE  OF  PISTON  PACKING  RING. 

and  the  ring  turned  down  to  the  proper  diameter  to  fit  the 
bore  of  the  cylinder  tube  easily. 

The  ring  is  then  reversed  in  the  chuck  and  held  by  the 
shoulder,  as  shown  in  Fig.  64. 

The  back  of  the  ring  is  then  finished  and  faced  off,  as 
shown. 

When  the  piston  and  ring  are  finished,  three  clearance 
holes  are  drilled  in  the  ring  for  No.  6  machine  screws,  by 
which  the  ring  is  secured  to  the  piston. 

Place    the    piston    and    ring  in    the    cylinder    and    mark 


PISTON. 


117 


through  the  clearance  hole  in  the  ring,  the  position  of  one 
of  the  screws  in  the  piston. 

Remove  the  piston  from  the  cylinder  and  drill  and  tap  a 


FIG.  64.— FINISHING  OUTSIDE  OF  PISTON  PACKING  RING. 

hole  for  a  No.  6  screw.  Replace  the  piston  and  ring  in  the 
cylinder  and  fasten  together  by  one  screw,  when  they  can 
be  removed  from  the  cylinder  and  the  remaining  two  screw 
holes  drilled  and  tapped. 

Several  who  have  built  engines  from  these  designs  have 
asked  for  a  more  permanent  packing  than  the  asbestos  wick- 
ing.  We  show  here  a  design  which  can  be  utilized  in  all 
future  engines  or  applied  to  those  already  built. 

These  parts  consist  of  two  cast-iron  rings  cut  apart  and 
sprung  into  the  cylinder.  These  rings  take  the  place  of  the 
asbestos  packing  and  are  held  in  place  by  a  follower  ring 
which  corresponds  to  the  packing  ring  already  described. 


iiS 


GAS   ENGINE   CONSTRUCTION. 


The  piston  rings  should  both  be  turned  from  one  end  of  a 
cast-iron  r-ing  while  the  other  end  is  held  in  the  jaws  of  the 
chuck. 

The  casting  for  the  rings  should  therefore  be  an  inch  long 
at  least. 

In  making  up  the  pattern  have  the  outside  diameter  2  J-J 
inches  and  the  inside  diameter  2T1¥  inches. 

Hold  one  end  of  the  cast  ring  in  a  three-jaw  chuck  and 
bore  out  the  inside  to  a  finished  diameter  of  2  -J-J-  inches.  It 
will  be  seen  on  referring  to  Fig.  64  A  that  the  rings  are  -A- 


tPISTON  RINGS 

SECTION  OF  PISTON, 
Rlf'GS  AND  FOLLOWER. 


END  VIEW'OF  RINGS. 

FIG.  64  A. 


SIDE  VIEW  OF  BIN  IS. 


inch  thick  on  one  side  and  thinner  on  the  other.  To  accom- 
plish this  open  the  chuck  jaws,  after  the  inside  of  the  ring 
casting  is  bored  out,  and  place  a  piece -of  metal  about  ¥^  inch 
thick  under  one  of  the  jaws.  This  will  force  the  casting  to 
one  side,  and  the  result  will  be  that,  when  finished,  the  ring 
will  be  thickest  on  one  side  and  gradually  taper  to  the 
thinnest  part  of  the  ring  directly  opposite. 

The  outside  of  the  casting  is  now  to  be  turned  down  to 
a  diameter  of  2  fj  inches  and  long  enough  to  cut  off  both 
rings.  Turn  as  smooth  as  possible  and  polish  with  emery 
cloth. 

Face  up  the  end  of  the  casting  true  and  then  with  a  good, 


PISTON.  IIQ 

• 

sharp  cut-off  tool  in  the  slide  rest  cut  off  a  ring  T3¥  inch  long. 
Face  up  the  end  of  the  casting  again  and  cut  off  the  second 
ring. 

The  rings  are  now  to  be  sawed  through  at  their  thinnest 
point,  as  shown  in  the  view  at  the  extreme  right  in  Fig. 
64  A.  In  order  to  spring  the  rings  sufficiently  to  place 
them  in  the  cylinder,  the  portions  inclosed  in  the  dotted 
lines,  and  marked  X,  must  be  cut  away.  This  must  be  done 
very  carefully,  using  a  small  flat  file.  The  rings  can  now  be 
sprung  together  to  place  in  the  cylinder,  and  the  joint  will 
have  the  appearance  shown  in  the  side  view. 

When  placed  in  the  cylinder  the  joints  of  the  rings  should 
be  at  opposite  sides  of  the  cylinder.  To  maintain  them  in 
their  relative  positions,  a  small  pin  is  inserted  in  one  of  the 
rings  and  one  end  allowed  to  project  into  a  larger  hole 
drilled  into  the  other  ring,  as  shown  in  the  sectional  view. 

The  follower  is  very  similar  in  shape  to  the  packing  ring 
described  in  this  chapter.  When  finished  it  should  be  turned 
down  to  a  diameter  of  2\  inches  where  the  rings  fit  over 
it.  It  should  not  touch  the  inside  of  the  rings  at  any  point. 
The  follower  is  held  against  the  piston  in  the  same  manner 
as  the  packing  ring,  by  three  No.  6-32  screws. 

The  instructions  given  for  turning,  finishing  and  fitting 
the  packing  ring  are  applicable  to  this  piece. 


Chapter   X. 
CONNECTING    ROD. 

CHUCKING    PISTON    PIN     END.       FITTING    IN    STEEL    CENTER 

CRANK     PIN     END.        CUTTING     APART     AND      FITTING. 

CHUCKING.       DRILLING,    BORING   AND    REAMING 

DRILLING  FOR   STEEL   CENTER.      TURNING 

AND    FITTING    STEEL    CENTER. 

TAPERING   PIN. 


CHAPTER  X. 

CONNECTING   ROD. 

The  connecting  rod  is  built  up  of  four  separate  pieces 
aside  from  the  two  fillister  head  screws  required  to  bolt 
together  the  crank-pin  end. 

The  brass  ends  should  be  finished  first,  as  the  holes  into 
which  the  steel  rod  is  to  be  driven  should  be  bored  before 
the  ends  of  the  rod  are  turned  down. 

The  piston  pin  end  is  chucked  by  the  cylindrical  part,  as 
shown  in  Fig.  65. 

Center  the  casting  with  a  tool  in  the  slide  rest  and  drill 
the  hole  with  about  a  T\-inch  drill. 

Set  a  boring  tool  in  the  slide  rest,  bore  out  to  scant  -J  inch 
and  finish  with  a  ^-inch  reamer. 

Fig.  65  shows  the  boring  tool  in  operation  and  the  reamer 
at  hand  to  gauge  size  of  hole. 

In  chucking  be  sure  that  the  boss  of  the  casting,  into  which 
the  steel  rod  is  to  fit,  is  parallel  with  the  face  of  the  chuck. 

After  reaming  the  hole  for  piston  pin,  face  off  the  outside 
of  the  casting. 

In  boring  the  boss  to  fit  on  steel  rod,  fasten  the  casting 
to  the  angle  plate,  as  shown  in  Fig.  66,  by  using  the  -|-inch 
pin  of  angle  plate  and  clamping  down  by  means  of  washers, 
etc.,  which  build  up  to  the  height  of  the  pin. 

Face  off  the  end  of  the  boss  and  center  it  with  a  tool  in 
the  slide  rest. 


122 


GAS    ENGINE    CONSTRUCTION. 


CONNECTING   ROD, 


123 


124  GAS   ENGINE   CONSTRUCTION. 

Drill,  bore  and  ream  the  hole  to  f-inch  diameter  and  -J-inch 
deep. 

Finish  the  outside  of  the  boss  while  in  this  position. 

If  the  crank  pin  end  of  the  rod  is  cast  in  one  piece  it  must 
first  be  center-punched  and  drilled,  as  shown  in  Fig.  67, 
using  a  No.  4  twist  drill.  Center-punch  a  hole  for  the 
drill  to  start  in,  and  directly  opposite  that  a  hole  for  the  back 
center  of  the  lathe  to  rest  in  while  the  casting  is  being 
drilled. 

Care  must  be  exercised  to  prevent  drilling  through  too 
far  and  either  damaging  the  drill  or  the  back  center.  A  hole 
can  be  drilled  with  much  more  certainty  of  going  straight 
through  in  this  manner  against  the  center  than  to  attempt 
holding  the  uneven  surface  of  the  casting  against  a  flat 
surface. 

Examine  the  depth  of  the  hole  frequently,  and  when  it  is 
found  that  the  drill  is  almost  through  remove  the  back  center 
and  finish  by  forcing  the  tail  stock  of  the  lathe  against  the 
casting. 

In  drilling  brass  with  a  twist  drill  the  work  should  always 
be  held  firmly  against  the  tail  stock  when  the  drill  is  about 
to  come  through,  as  the  tendency  at  that  time  is  for  the  drill 
to  catch  and  the  work  to  travel  up  the  spiral  groove.  Woe 
be  to  the  fingers  which  are  attempting  to  hold  an  angular 
piece  of  brass  when  this  happens  and  the  said  piece  catches 
and  begins  to  travel  around  at  the  same  rate  as  the  drill ! 

After  both  holes  are  drilled  cut  the  casting  apart  with  a 
hack  saw  through  the  center  of  the  bearing.  The  two  pieces 
must  now  be  filed  and  fitted  together. 

The  holes  in  the  outer  piece  are  to  be  enlarged  to  ^-inch 
and  the  holes  in  the  inner  piece  tapped  with  a  14-20  tap. 
The  two  pieces  are  now  to  be  fastened  together  with  cap 
screws  and  bored  out  to  fit  the  crank  pin. 


CONNECTING   ROD. 


125 


03 
O 


126 


GAS   ENGINE   CONSTRUCTION. 


CONNECTING    ROD. 


127 


In  chucking  this  end  of  the  connecting  rod  some  little 
ingenuity  may  be  necessary  to  hold  it  in  a  three-jawed 
chuck. 

Fig.  68  shows  the  parts  chucked  with  a  small  piece  of  brass 
rod  used  as  a  packing  piece  to  fill  out  the  lower  side.  In 
this  case  a  notch  had  to  be  filed  in  the  piece  of  rod  to  make 
it  the  proper  thickness. 

When  in  position  face  off  and  center  with  a  tool  in  the 
slide-rest.  Drill,  bore  and  ream  out  to  f-inch  size. 


FIG.  69. — DRILLING  AND  REAMING  CONNECTING  ROD  HEAD 
TO  FIT  ROD. 

The  parts  can  be  removed  from  the  chuck  and  clamped  to 
the  angle  plate  for  boring  out  boss  for  steel  rod.  Fig.  69 
shows  the  operation.  The  J-inch  pin  of  the  angle  plate  must 
be  bushed  to  fit  the  f-inch  hole,  and  the  parts  clamped  in 
position.  As  will  be  seen,  this  operation  is  identical  with 
the  one  described  for  the  piston  pin  end  of  the  connecting 
rod.  The  only  difference  shown  is  in  method  of  clamping 


128 


GAS   ENGINE   CONSTRUCTION. 


to  the  angle  plate.  In  this  cut  a  piece  of  brass  tubing  is  used, 
instead  of  washers,  to  build  up  the  casting  to  the  height  of 
the  angle  plate  pin. 

Drill,  bore  and  ream  a  f-inch  hole  in  boss  of  casting,  f-inch 
deep. 

The  two  rod  ends  must  be  faced  up  true  with  the  holes 
for  crank  pin  and  piston  pin.  This  is  done  on  an  arbor  or 
mandrel,  as  shown  in  Fig.  70.  This  mandrel  is  made  from 


FIG.  70. — TURNING  AND  FINISHING  CONNECTING  ROD  HEAD. 

any  piece  of  iron  or  steel  which  is  found  suitable.  In  this 
cut  it  will  be  seen  that  the  end  of  the  arbor  next  the  back 
center  has  been  turned  down  to  ^-inch  diameter  to  fit  the 
piston  pin  end  of  the  rod  and  the  next  section  is  turned  to 
f-inch  diameter.  The  crank  pin  end  of  the  rod  is  in  position 
ready  for  facing  up.  This  is  best  done  by  using  right  and 
left  side  tools  on  the  alternate  sides  of  the  parts.  The  most 
important  thing  in  connection  with  this  operation  is  to  leave 


CONNECTING   ROD. 


I29 


both  faces  at  an  equal  distance  from  the  sides  of  the  finished 
boss. 

The  arbor  should  be  turned  a  little  full  in  size  and  then 
filed  slightly  tapering  toward  the  tail  stock  to  allow  the  rod 
ends  to  be  driven  on  tight  enough  to  retain  their  position 
while  being  faced. 

Referring  to  Fig.  71  it  will  be  seen  that  the  center  section 
of  the  connecting  rod  is  turned  from  a  piece  of  f-inch 
machinery  steel,  9^f  inches  long. 

Center  the  ends  carefully  and  drill  them  for  about  T3^-inch 
with  small  drill,  after  which  use  a  center  reamer. 

Place  in  the  lathe,  between  the  centers,  and  turn  down 
each  end  to  a  full  f-inch  for  a  distance  of  J4nch,  squaring  up 
the  shoulders  with  a  sharp  side  tool. 

Leave  a  collar  T3^-inch  wide  at  each  shoulder  and  turn  down 
behind  each  collar  a  neck  of  the  rod  ^-inch  in  diameter. 
•  Swivel  the  slide  rest,  or,  if  an  engine  lathe  is  used,  set  over 
the  tail  stock  until  a  cut  started  at  the  neck  of  the  rod  would 
just  run  out  at  the  center.  In  a  light  lathe  two  or  more  cuts 
will  have  to  be  made  to  straighten  this  across. 

Stop  the  tool  ^-inch  from  the  center  of  the  rod. 

Turn  the  rod  around,  cut  the  other  end  in  the  same  man- 
ner. This  will  leave  a  portion  of  the  rod,  in  the  center,  of  the 
original  diameter  and  i  inch  in  length,  with  a  slight  shoulder 
at  each  end,  which  adds  very  much  to  its  appearance. 

File  up  with  a  smooth  file  and  finish  with  fine  emery 
cloth. 

In  assembling  the  parts  of  the  connecting  rod  it  is  import- 
ant that  the  holes  for  crank  pin  and  piston  pin  should  be  in 
line. 

This  is  best  accomplished  as  shown  in  Fig.  72. 

In  this  cut  the  piston  pin  end  of  the  rod  has  been  drilled 
through  the  brass  boss  and  steel  rod  and  a  small  pin  made 


130 


GAS   ENGINE   CONSTRUCTION. 


CONNECTING   ROD. 


of  steel  wire  driven  through.  A  -J-inch  reamer  was  then 
placed  in  the  hole  for  the  piston  pin  and  a  piece  of  f -inch  rod 
in  the  crank  pin  hole.  In  sighting  across  the  reamer  and 
rod,  if  they  are  exactly  parallel,  the  rod  is  in  line.  If  not 
parallel,  the  free  end  of  the  rod  must  be  turned  until  the 
holes  are  exactly  in  line,  after  which  the  remaining  end  is 
drilled  and  a  pin  inserted.  It  will  be  found  advisable  to 
ream  these  pin  holes  with  a  small  five-sided  brooch  or  reamer 
and  use  taper  pins  to  fit  them. 


FIG.  72. — PUTTING  CONNECTING  ROD  ENDS 

IN 


Chapter  XL 
BEARINGS. 


CHUCKING   THE   CASTINGS.      DRILLING,  BORING  AND  REAMING 
FOR     SHAFT.       ATTACHING     TO     ANGLE     PLATE.       LINING 
UP    THE    PLATE.       INSERTING    PIN    BUSHINGS.       CEN^ 
TERING    AND    BORING    FOR    SIDE    RODS.       TURN- 
ING   TO    FACE    OFF    BASE.        CYLINDER    SUP- 
PORTS.     CHUCKING  AND    BORING.      FAC- 
ING  BASE.      DRILLING  FOR  SCREWS. 
HUB  FOR  GEAR   STUD.      DRILL- 
ING.     OIL   CUPS. 


CHAPTER  XI. 

BEARINGS,    ETC. 

The  castings  for  the  main  bearings  should  first  be  chucked 
to  bore  out  for  the  shaft,  as  shown  in  Fig.  73. 

With  a  round  point  tool  in  the  slide  rest  face  off  the  end 
of  the  bearing,  then  make  an  indentation  in  the  end  of  the 
bearing  \vith  the  centering  tool  while  the  piece  of  work  is 
revolving. 

This  should  be  made  quite  deep  and  must  run  true. 

With  a  f-inch  drill  (either  flat  or  twist  drill  will  do)  held 
against  the  back  center  of  the  lathe,  as  shown  in  Fig.  73, 
start  the  drill  through  the  casting  where  the  indentation  is, 
made. 

Before  the  hole  is  drilled  entirely  through  it  will  probably 
be  noticed  that  the  drill  is  wabbling  more  or  less,  and  when 
the  hole  is  drilled  it  will  run  unevenly.  This  must  now  be 
trued  up  by  using  a  boring  tool  in  the  slide  rest. 

Bore  out  by  taking  light  cuts  until  the  end  of  the  reamer 
will  enter  the  hole,  then  ream  to  size,  which,  in  this  engine, 
will  be  f  inch. 

After  both  bearings  have  been  bored  and  reamed  for  the 
shaft  they  must  be  drilled  and  bored  for  the  side  rods. 

For  this  operation  the  angle  plate  is  used. 

Place  the  angle  plate  on  the  face  plate,  with  a  piece  of 
newspaper  between,  and  insert  the  bolts.  Place  the  steel 
pin  in  position  in  the  angle  plate  shelf  and  place  on  the  pin 


136 


GAS   ENGINE   CONSTRUCTION. 


C/3 

I 

O 
g 

i 

PQ 


BEARINGS,  ETC. 


137 


one  of  the  bushings.  A  small  piece  of  newspaper  should  be 
previously  put  on  over  the  pin.  It  may  be  well  to  state  that 
the  purpose  in  placing-  a  piece  of  paper  on  the  angle  plate 
shelf,  and  between  it  and  the  face  plate,  is  that  the  two  smooth 
surfaces  of  the  metal  will  not  adhere  as  well  under  a  given 


CAST  IRON 

MAKE  ONE 


FIG.  74. — BEARINGS. 

pressure  when  put  together  surface  to  surface  as  they  will 
if  a  thin  piece  of  soft  paper  is  inserted  between.  This  is  a 
good  wrinkle  to  remember  in  clamping  up  work. 

After  the  first  bushing  is  in  place  set  the  bearing  on  over 
it  and  then  place  the  second  bushing  over  the  pin  and  down 


138 


GAS   ENGINE   CONSTRUCTION. 


into  the  top  of  the  hole  in  the  bearing.  Build  up  on  top  of 
the  casting  with  washers  until  they  exceed  the  height  of  the 
pin,  when  a  large  washer  with  small  hole  to  fit  the  J-inch 
cap  screw  is  placed  across  the  top  and  the  bearing  clamped 


>  FINISHED  SURFACE 


CAST  IRON 
MAKE  ONE 


STUBS  STEEL 
MAKE  ONE 


FIG.  75.  —  BEARINGS. 


down  on  the  shelf  of  the  angle  plate.  The  plate  must  now 
be  adjusted  up  or  down  on  the  face  plate  until  the  center  of 
the  boss  for  the  side  rod  is  in  line  with  the  back  center.  The 
boss  of  the  bearing  should  also  be  in  line  with  the  lathe  bed 
and  run  true  when  the  lathe  spindle  revolves. 


BEARINGS,  ETC.  139 

Fig.  76  shows  the  bearing  in  position  on  the  angle  plate. 
Center  the  end  of  the  boss  by  using  the  centering  tool  in  the 
slide  rest,  or  a  hand  tool. 

Drill  into  the  end  of  the  boss  with  about  a  T\-inch  drill  to 
a  depth  of  i£  inches.  Set  a  boring  tool  in  the  slide  rest  and 
bore  out  the  hole  until  the  end  of  a  J-inch  reamer  will 
enter.  Ream  to  size  with  the  lathe  revolving  at  very  slow 
speed. 

Fig.  76  shows  the  boring  tool  in  operation  and  the  reamer 
on  the  slide  rest  ready  to  use  for  gauging  the  diameter  of 
the  hole. 

The  ends  of  the  boss  of  each  bearing  must  be  faced  off  at 
an  equal  distance  from  the  hole  for  the  shaft.  An  easy  way 
to  determine  this  is  to  face  off  the  first  bearing  and  measure 
with  a  pair  of  dividers  the  distance  from  the  end  of  the  boss 
to  the  back  of  the  angle  plate.  Keep  the  dividers  set  at  the 
same  measurement  until  the  boss  of  the  second  bearing  is 
ready  to  be  faced,  when  the  dividers  can  be  used  to  gauge 
the  length  of  it. 

After  finishing  the  second  bearing  the  cap  screw  in  the 
angle  plate  pin  can  be  loosened  and  the  bearing  swung 
around  until  the  foot  of  the  bearing  is  in  position  to  face  off. 

Fig.  77*   shows  the  bearing  in  position. 

A  -J-inch  reamer  is  placed  in  the  hole  of  the  boss,  by  which 
it  is  lined  up.  If  one  side  of  a  steel  square  is  now  held 
against  the  side  of  the  reamer  the  other  side  of  the  square 
should  be  in  line  with  the  lathe  bed. 

This  will  bring  the  hole  in  the  boss  and  the  bottom  of  the 
bearing  parallel  when  the  base  has  been  faced  off. 


*  It  will  be  noted  that  in  this  cut  the  screw  holes  in  the  base  have 
been  bored.  This  photo  had  to  be  retaken,  and  the  bearing  was  removed 
from  the  finished  engine  for  that  purpose,  the  first  plate  having  been 
spoiled. 


140 


GAS    ENGINE   CONSTRUCTION, 


BEARINGS,  ETC. 


T 


142 


GAS   ENGINE   CONSTRUCTION. 


Set  a  round  point  tool  in  the  slide  rest  to  face  across  the 
bottom  of  the  bearing. 

After  the  cut  is  made  across  the  bottom  the  operator  should 
run  the  slide  rest  toward  him  by  using  the  cross-feed  only, 
and  remove  the  bearing  from  the  angle  plate.  Place  the 
second  bearing  in  position  and  feed  the  slide  rest  toward 
the  work  by  the  cross-feed  only.  If  cut  across  in  this  way 
the  bearings  will  be  of  exactly  the  same  height  from  the 
bottom  to  the  shaft. 


-+  — ,» 


~p~j 


A— 


m$ 

FINISHED  SURFACE 


.1 


4 

:f 


SECTION  THR.    A-B 


CAST   IRON 

MAKE  TWO 


FIG.  78.— SUPPORTS. 

The  supports  for  the  cylinder  are  to  be  done  in  the  same 
manner  as  the  main  bearings,  being  first  chucked  by  their 
cylindrical  parts  and  drilled,  bored  and  reamed  to  ^  inch, 
after  which  they  are  placed  on  the  angle  plate  pin  and  the 
bottom  faced  off. 

It  will  be  found  advisable  to  do  the  drilling,  boring  and 
reaming  of  the  cylinder  supports  before  the  angle  plate  is 
placed  in  position,  as  they  can  then  be  faced  off  on  the  bot- 
tom by  placing  on  the  angle  plate  pin  as  soon  as  the  bearings 


BEARINGS,  ETC. 


'43- 


w 


144 


GAS    ENGINE    CONSTRUCTION. 


are  faced  off  and  a  cut  taken  across  them  while  the  tool  is 
adjusted  for  the  bearings. 

This  will  bring  all  four  pieces  exactly  the  same  height 
from  the  bottoms  to  the  center  of  the  holes. 

After  the  bearings  and  supports  have  been  faced  the  holes 


FIG.  80. —DRILLING  MAIN  BEARING  ON  DRILL  PRESS, 

are  to  be  drilled  in  the  bottom,  by  which  they  are  to  be 
fastened  to  the  bed  plate.  The  position  of  the  screws  and 
cap  screws  are  laid  off  on  the  bottom  of  the  castings  with 
a  pair  of  dividers.  The  positions  laid  off  are  then  center- 
punched.  In  drilling  the  bearings  for  cap  screws  use  a  J-inch 


BEARINGS,  ETC. 


145 


5 
P 
x 

n 
3 

g 

$9 

CA2 

<2 
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I 


146 


GAS   ENGINE   CONSTRUCTION. 


BEARINGS,  ETC.  f  147 

drill  and  hold  the  bearings  on  the  angle  plate  pin,  as  shown 
in  Fig.  79. 

Fig.  80  shows  the  same  operation  as  it  would  be  done  on 
an  upright  drill  press. 

The  cylinder  supports  are  also  to  be  drilled  for  screws. 
Lay  off  the  holes  in  their  proper  location,  then  center-punch 
them  and  drill  when  clamped  on  the  angle  plate  pin,  as 
shown  in  Fig.  81. 


FIG.  83. — SMALL  LUBRICATOR 
•    FOR  BEARINGS. 

One  of  the  main  bearings  has  a  small  hub  cast  on  the  boss 
for  the  gear  stud. 

Lay  off,  with  the  dividers,  a  point  on  this  hub  i£  inches 
from  the  center  of  the  hole  for  the  shaft.  Center-punch  this 
point  and  drill  a  T5¥  inch  hole  for  the  stud.  To  drill  the 
hole  the  bearing  should  be  clamped  to  the  angle  plate  and 
drilled,  as  shown  in  Fig.  82. 

Oil  cups  are  to  be  placed  on  the  bearings.  Center-punch 
the  bearing  directly  over  the  shaft.  Use  a  ^-inch  drill, 
placing  the  base  of  bearing  against  the  the  tail  stock  of  the 
lathe. 


148  GAS   ENGINE   CONSTRUCTION. 

Drill  the  bearings  to  a  depth  of  about  Jinch,  after  which 
the  holes  are  to  be  continued  through  to  the  shaft  with  a 
smaller  drill — No.  42  will  do  for  this. 

The  oil  cups  can  be  turned  up  by  hand  from  a  piece  of 
-J-inch  brass  rod. 


Chapter  XII. 
SIDE  RODS. 

CENTERING.       LENGTH.       SHOULDERS.       TURNING.       FITTING. 
FILING.      FINISHING.       THREADING.       TESTING  ACCU- 
RACY   OF    PREVIOUS    WORK.        DRILLING 
AND   FILING   FOR   KEYS. 


CHAPTER     XII. 

SIDE    RODS. 

The  side  rods  are  made  of  soft  steel  bars  f  inch  in  diame- 
ter and  i6f  inches  long. 

In  turning  these  rods  on  a  plain  lathe  with  a  slide  rest, 
care  must  be  exercised  to  have  the  slide  rest  set  squarely  on 
the  lathe  bed,  and  that  the  tool  travels  parallel  with  the  rod 
to  be  turned. 

Use  a  sharp  side  tool  to  turn  down  the  ends  and  finish 
the  shoulders. 

After  the  slide  rest  is  set  and  the  first  cut  taken,  caliper 
the  work  at  each  end  of  the  cut.  If  it  is  found  that  the  two 
diameters  are  not  exactly  the  same,  the  slide  rest  must  be 
loosened  and  reset.  If  the  difference  is  very  slight,  a  light 
tap  on  the  proper  side  of  the  slide  rest  with  a  mallet  will  be 
found  to  correct  the  fault. 

Be  sure  to  clean  out  the  corners  of  the  shoulders  at  each 
end  of  the  rod,  to  allow  the  bearings  and  cylinder  lugs  to 
come  square  up. 

The  ends  of  the  rods  which  fit  into  the  boss  of  the  bear- 
ing must  be  slightly  tapered  at  the  ends  to  correspond 
with  the  taper  of  the  end  of  the  reamer.  This  may  be 
done  with  a  file  while  the  rod  is  revolving  in  the  lathe,  but 
care  must  be  used  that  only  just  sufficient  material  is 
removed  to  make  the  rod  a  tight  fit  into  the  boss. 

In  finishing  the  center  portion  of   the  side   rods   be  sure 


GAS   ENGINE   CONSTRUCTION. 


oteJ" 

nrl 

i     1 1 
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Lj 


ij 


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o 

rt 

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y     co 


that  the  distance  between  the  shoulders 
is  exactly  the  same,  otherwise  the  cylin- 
der and  shaft  will  be  cramped  when  the 
parts  are  put  together  and  fastened. 

If  a  plain  side  rest  is  used  in  turning 
these  rods,  it  may  be  necessary  to  set  it 
in  two  different  positions  on  the  lathe 
bed,  as  the  travel  of  the  tool  post  may 
not  be  sufficient  to  turn  the  lengths  of 
cut  required  at  one  setting.  In  this 
case,  when  the  slide  rest  is  moved,  be 
sure  there  are  no  chips  or  cuttings 
under  the  base  of  the  rest,  as  they 
would  tend  to  prevent  accurate  work. 

In  Fig.  85  is  shown  a  side  tool  in  the 
slide  rest  finishing  the  long  cut  on  the 
cylinder  end  of  one  of  the  rods.  It  will 
be  noticed  that  the  metal  is  cut  from  the 
work  in  long  spiral  coils,  one  of  which 
is  seen  at  the  point  of  the  tool. 

The  red  is  turned  down  along  the 
center  between  the  two  shoulders,  but 
at  each  end  of  the  cut  a  collar  is  left 
the  original  diameter  of  the  rod,  which 
adds  very  much  to  the  appearance  when 
finished. 

After  being  turned  to  size,  the  center 
part  should  be  filed  as  smooth  as  possi- 
ble and  polished  with  emery  cloth. 

Fig.  85  shows  one  rod  finished  and 
ready  for  threading. 

Should  the  builder  possess  an  engine 
lathe,  the  rods  can  be  threaded  easily 


SIDE    RODS. 


153 


CO 
Cn 


154 


GAS   ENGINE   CONSTRUCTION. 


and  accurately,  but  the  cuts  taken  with  the  threading  tool 
must  be  very  light,  as  otherwise  the  work  will  spring,  being 
so  long  and  of  small  diameter. 

If  done  by  hand  with  a  £-inch  die,  the  thread  must  be 
started  very  carefully  to  prevent  the  die  from  running  in  on 
one  side,  as  it  will  sometimes  cut  away  the.  material  to  quite 
an  extent,  thus  weakening  the  rod  at  that  point,  and  further, 
more,  the  nut  will  not  bear  squarely  on  the  cylinder  collar. 

At  this  point  the  accuracy  of  the  work  may  be  tested,  as 


FIG.  86. — CYLINDER  COLLARS,  SIDE  RODS  AND  MAIN  BEARINGS 
ASSEMBLED  TO  TEST  ACCURACY  OF  WORK. 

shown  in  Fig.  86.  This  shows  the  cylinder  collars,  brass 
jacket  shell,  cylinder  supports,  side  rods,  and  bearings  placed 
in  position,  which  should  be  done  on  a  perfectly  level  sur- 
face. When  these  parts  are  assembled  in  their  proper  posi- 
tions and  a  solid  shaft  placed  through  the  bearings,  if  the 
lathe  work  has  been  accurately  done,  the  shaft  can  be  easily 
rotated  between  the  fingers. 

The  rods  are  secured  to  the  bearings  by  keys  driven 
through  the  boss  and  the  rod,  as  shown  in  Fig.  88. 

Center- punch  the  top  of  the  boss  f  inch  from  its  outer  end 


SIDE   RODS. 


155 


If, 


'56 


GAS   ENGINE   CONSTRUCTION. 


and  lay  off  with  the  dividers  another  point  -£%  inch  from  the 
first  center-punch  mark  toward  the  shaft,  which  also  cen- 
ter-punch. 

Fasten  the  bearing  to  the  angle  plate  by  a  J-inch  cap 
screw,  as  shown  in  Fig.  87, 

Drill  directly  through  the  boss  and  side  rod  at  both  cen- 
ter-punch marks  with  a  ^-inch  drill. 

In  drilling  this  in  the  lathe,  do  not  let  any  of  the  weight 
of  the  angle  plate,  etc.,  hang  on  the  drill,  as  it  will,  in  that 
case,  run  out  of  place,  and  the  two  holes  will  not  be  parallel. 
Also  see  that  the  side  rod  remains  in  position  until  the  drill 


FIG.  88. — SIDE  ROD  AND  MAIN  BEARING  KEYED  TOGETHER. 

« 

has  passed  through.  When  finished  there  will  be  two  par- 
allel holes  ^g-  inch  apart.  Remove  the  rod  and,  using  a  small 
round  file,  cut  away  the  metal  between  the  two  holes  in  the 
rod  ;  they  will  then  form  a  slot  -J  inch  by  -/y  inch.  File 
away  the  rod  about  -fw  inch  more  toward  the  shoulder. 

The  holes  in  the  bearings  must  now  be  filed  into  a  slot, 
after  which  the  slot  is  filed  another  F^  inch  toward  the  shaft. 

When  the  parts  are  put  together  now,  a  taper  key  -J  inch 
thick  driven  through  the  slots  will  draw  the  rod  into  the 
bearing,  as  shown  in  the  cross  section  in  Fig.  88.  The  key 
should  be  made  of  steel.  . 


Chapter  XIII. 
BED    PLATE. 

FILING.      PLANING.       LINING   UP.      AN     IMPROVED     FORM. 


CHAPTER     XIII. 

BED    PLATE. 

The  bed  plate  casting-  requires  very  little  work,  yet  to  the 
amateur  this  little  may  present  some  difficulties. 

The  four  points  on  which  the  engine  proper  rests  require 
to  be  perfectly  level. 

The  only  way  in  which  this  can  be  done  with  perfect 
accuracy  is  on  a  planer  or  a  milling  machine.  The  four  sur- 
faces can  be  filed  down  if  the  operator  has  sufficient  patience, 
but  it  would  be  preferable  to  take  the  piece  to  a  machine 
shop  or  procure  the  casting  already  planed. 

If  it  is  decided  to  work  the  casting  down  by  filing,  it  will 
be  first  necessary  to  ascertain  how  the  parts  line  up  in  the 
rough,  which  stand  the  highest  and,  in  consequence,  require 
the  most  filing. 

In  determining  this,  set  the  bed  plate  on  a  sufficient  eleva- 
tion and  use  the  two  pieces  of  straight  steel  rods  before 
turning  them  for  side  rods,  or  the  two  pieces  of  f  inch  steel 
shaft  may  be  used  ;  place  one  across  the  tops  of  the  raised 
surfaces  where  the  main  bearings  are  to  stand  and  the  other 
across  the  surfaces  where  the  supports  for  the  cylinder  are 
to  be  placed.  If  the  eye  is  brought  to  the  same  level  and 
sighted  across  the  tops  of  the  two  rods,  it  will  be  readily 
seen  which  surface  is  the  highest. 

Now  change  the  position  of  the  rods,  resting  one  end  of 
each  one  on  a  main  bearing  surface  and  the  other  end  of 


i6o 


GAS   ENGINE   CONSTRUCTION. 


each  on  a  cylinder  support  surface.  Sight  across  the  rods 
as  now  placed  and  it  will  be  apparent  which  surfaces  require 
the  most  filing.  Continue  using  the  steel  rods  at  intervals 
to  test  the  accuracy  of  the  work  while  filing  the  bearing 
surfaces. 


IMPROVED  FORM  OF  BED  PLATE. 

This  form  of  bed  plate  gives  the  engine  a  neater  appear- 
ance when  completed,  but  as  the  pattern  work  is  much  more 
difficult  we  should  not  advise  the  amateur  to  attempt  it. 


Chapter  XIV. 
FLY-WHEELS    AND    SHAFT. 

SIMPLE  ARRANGEMENT  OF  FACE   PLATE  FOR  TURNING.      BOLT- 
ING TO  FACE   PLATE.      CENTERING,  BORING  AND  REAMING 
FOR    SHAFT.       FACING    HUBS.        BORING    CRANK    PIN 
HOLES.       SHAFT.       DIMENSIONS.       FITTING   GEAR 
WHEEL  TO  SHAFT.      DRILLING  AND    PINNING 
FLY-WHEELS     TO     SHAFT.        EXTENDING 
DRILL.      CRANK    PIN. 


CHAPTER    XIV. 

FLY-WHEELS   AND    SHAFT. 

To  turn  and  finish  the  fly-wheels  of  an  engine  this  size,  a 
lathe  swinging  18  inches  is  required.  This  is  the  only  part 
of  the  work  an  amateur  with  a  small  lathe  will  be  unable  to 
accomplish.  These,  however,  may  be  obtained  already 
finished. 

In  turning  up  the  wheels,  the  best  and  cheapest  arrange- 
ment for  the  purpose  is  shown  in  Fig.  89.  The  face  plate  in 
this  case  was  about  8  inches  in  diameter.  A  piece  of  hard- 
wood board  was  cut  off  the  same  length  and  width  as  the 
diameter  of  the  face  plate,  and  after  the  corners  had  been 
cut  off,  it  formed  an  octagon,  as  shown.  This  was  fastened 
to  the  face  plate  by  four  wood  screws,  with  washers  under 
the  heads,  which  passed  through  the  slots  in  the  face  plate. 
The  front  of  the  hardwood  board  was  then  faced  off  true  and 
a  recess  cut  out  at  the  center  for  the  fly-wheel  hub.  Two 
^  inch  holes  were  bored  through  the  wood  at  opposite  slots 
in  the  face  plate,  through  which  were  inserted  the  two  bolts 
for  holding  the  fly-wheel.  The  bolt  heads  can  be  seen  in 
the  cuts.  The  bolts  came  through  between  two  of  the  arms 
on  opposite  sides  of  the  wheel,  and  washers  were  placed 
across  the  front  of  the  arms  and  the  wheel  bolted  to  the  face 
plate  thereby,  as  sho.wn  in  Fig.  90.  Tighten  the  nuts  just 
sufficiently  to  hold  the  wheel  from  slipping  while  the  lathe  is 
revolved  slowly  to  ascertain  if  the  wheel  runs  true.  If  the 


164 


GAS   ENGINE   CONSTRUCTION. 


FLY-WHEELS    AND    SHAFT.  165 

t 

wheel  is  not  in  proper  position,  a  light  blow  with  a  hammer 
is  sufficient  to  move  it  in  the  desired  direction. 

When  the  wheel  runs  sufficiently  true,  tighten  up  the  nuts 
and  it  is  ready  to  face  up. 

With  the  wheel  held  in  this  manner,  it  is  possible  to  turn 
up  and  finish  the  entire  rim  and  the  hub,  with  the  exception 


FIG.  90.— FLY-WHEEL  BOLTED  TO  FACE  PLATE. 

of  facing  the  side  of  the  hub  next  the  face  plate.  The  side 
of  the  rim  next  the  carriage  can  be  operated  on  with  a  plain 
round  point  tool. 

The  face  of  the  wheel  may  require  a  tool  with  its  point 
bent  at  a  right  angle  ;  this  depends  on  how  far  the  tool  post 
comes  toward  the  front  of  the  lathe.  The  side  of  the  rim 
next  the  lathe  head  will,  however,  require  a  special  tool 


1 66 


GAS   ENGINE   CONSTRUCTION. 


FLY-WHEELS  AND    SHAFT. 


I67 


bent  as  shown  in  operation  in  Fig.  89  and  described  in 
Chapter  7. 

This  tool  is  bent  around  in  a  semicircle  and  the  point 
turned  toward  the  carriage. 

This  plan  of  turning  the  wheel  will  be  found  preferable  to 
boring  for  shaft  first  and  then  placing  on  a  mandrel  to  turn 


FIG.  92. — PIN  FITTED  TO  FACE  PLATE. 


the  rim,  as  it  is  held  more  securely  in  this  manner  and  will 
not  chatter  if  the  lathe  head  is  in  order. 

In  finishing  the  hub  while  in  this  position,  first  face  off  the 
side  and  center  the  hole  with  the  proper  lathe  tools.  Drill, 
bore,  and  ream  to  size  of  shaft,  which  in  this  case  is  f  inch. 

The  wheel  can  now  be  removed  and  the  opposite  face  of 


163  GAS   ENGINE   CONSTRUCTION. 

the  hub  finished  by  placing  the  wheel  on  a  mandrel  between 
the  lathe  centers. 

When  both  wheels  have  been  finished  thus  far  they  are 
ready  for  the  crank  pin  holes.  These  must  be  drilled  very 
accurately  in  reference  to  their  distance  from  and  alignment 
to  the  holes  bored  for  the  shaft. 


FIG.  93. — DRILLING  FLY-WHEEL  FOR  CRANK  PIN. 

i 

To  do  this  accurately  a  soft  steel  pin  of  the  exact  diametc  r 
of  the  shaft  should  be  inserted  in  the  face  plate  at  a  distance 
from  the  center  exactly  corresponding  to  one-half  the  throw 
of  the  crank.  In  this  size  of  engine  the  distance  will  be  2 
inches. 

In  Fig.  92  will  be  seen  the  pin  inserted  in  the  face  plate, 


FLY-WHEELS   AND    SHAFT. 


169 


with  bolts  protruding-  from  two  of  the  slots  with  which  to 
clamp  the  wheel  to  the  face  plate.  In  this  cut  a  piece  of 
U-shaped  iron  is  shown  lying  on  the  front  of  the  lathe  bed^ 
through  which  the  bolts  pass,  as  shown  in  Fig.  93.  This 
clamps  the  wheel  by  the  hub  alone  and  will  hold  it  more 
accurately  than  if  the  two  bolts  clamped  the  arms  of  the 
wheel,  as  there  would  then  be  a  tendency  to  spring  the  stud 
on  the  face  plate  if  one  bolt  were  tighter  than  the  other. 


MACHINE  STEEL 

MAKE  ONE  OF   EACH 


FIG.  94. — FLY- WHEEL  SHAFTS. 

This  brings  the  crank  pin  boss  directly  over  the  hollow 
spindle  of  the  lathe  head,  where  it  can  be  drilled,  bored  and 
reamed  the  proper  size,  •£  inch,  and  the  hole  will  be  in  line 
with  the  hole  for  the  shaft. 

A  space  |  inch  in  diameter  should  be  faced  off  around  this 
hole,  while  the  wheel  is  in  this  position,  for  the  shoulder  of 
the  crank  pin  to  fit  against. 

The  crank  shaft  is  made  in  two  pieces.     The  shaft  on  the 


I/O  GAS   ENGINE   CONSTRUCTION. 

valve  gear  side  of  the  engine  should  be  4$  inches  long  and 
the  outer  end  should  be  turned  down  to  a  diameter  of  -J  inch 
for  a  distance  of  i-J-f  inch. 

This  is  done  in  order  to  fit  on  the  i  inch  gear  wheel  used 
to  drive  the  valve  mechanism. 

The  gear  wheel  should  be  chucked  and  bored  out  to  fit 
the  shaft,  after  which  the  hub  is  turned  and  finished. 

To  attach  the  I  inch  gear  to  crank  shaft,  drill  through  the 
hub  and  shaft  for  a  steel  pin,  using  about  a  No.  42  twist  drill. 
The  hole  may  be  tapered  with  a  five-sided  brooch  and  a 
taper  pin  filed  up  for  it  in  the  lathe. 


FIG.  95. — DRILLING  FLV-WHEEL  AND  SHAFT  FOR  PIN. 

On  the  turned  down  portion  of  the  shaft,  £  inch  from  the 
end,  drill  a  hole  through  the  shaft,  using  a  No.  19  twist  drill. 
A  steel  pin  f  inch  long  should  be  driven  through  this  hole. 
It  is  intended  to  form  a  clutch  for  the  starting  handle.  This 
portion  of  the  crank  shaft  is  shown  in  the  detail  drawings. 

The  other  portion  of  the  crank  shaft  is  7  inches  in  length 
and  full  diameter  for  its  entire  length. 

The  operation  of  drilling  the  fly-wheel  and  shaft  for  the 
purpose  of  fastening  them  securely  together  is  shown  in  Fig. 


FLY-WHEELS   AND    SHAFT.  I  /I 

t 

95.  The  drill  is  extended  by  using  apiece  of  brass  rod.  To 
make  the  extension,  drill  into  the  end  of  the  rod  with  a  drill 
about  one  size  smaller  than  the  one  to  be  used,  or  a  No.  20, 
for  a  distance  of  about  i  inch.  Hold  the  No.  19  drill 
securely  between  two  pieces  of  hardwood  or  fiber  in  the 
vise  and  drive  the  brass  extension  onto  it. 

Fig.  95  shows  clearly  the  wheel  blocked  up  to  the  proper 
height  and  fed  against  the  drill  by  the  tail  stock.  Use  steel 
wire  for  pins,  and  make  a  driving  fit. 

An  engine  built  on  this  plan,  with  the  fly-wheel  between 
the  bearings,  does  not  require  the  wheel  to  be  as  firmly  keyed 
to  the  shaft  as  one  having  the  wheels  outside  the  bearings. 
In  this  case  the  thrust  of  the  explosion  of  the  gas  is  delivered 
directly  to  the  fly-wheels  by  the  connecting  rod,  without 
exerting  a  torsional   strain 
on    the   shaft,  as  Avould   be 
the  case    were    the    wheels 
outside  the  bearings. 

U  -/i  •  7»»  -  *Jt*-  -  7^^          TAP  1$  20  THR. 

The  crank   pin   is  shown  MACHINE  STEEL 

E 


MAKE  ONE 


in    detail   in   Fig.  96,  which  FlG  96<.__CRANK  PlN> 

gives  all  dimensions.     This 

should  be  turned  from  a  piece  of  machinery  steel. 

After  the  bearing  part  of  the  pin  has  been  turned  to  size, 
finish  with  a  smooth  file  and  polish  evenly  with  fine  emery 
cloth. 

In  turning  up  the  pin  be  sure  to  have  the  two  shoulders 
faced  up  true  to  fit  against  the  crank  pin  bosses  on  the  fly- 
wheels. 

After  the  crank  pin  is  finished  to  size,  drill  into  each  end 
with  a  No.  4  twist  drill  to  the  depth  of  about  i  inch  and  tap 
the  holes  with  J  inch  —  20  tap. 

This  is  for  the  cap  screws  which,  with  a  washer  under  each, 
clamp  the  fly-wheels  securely  to  the  pin. 


1/2  GAS   ENGINE   CONSTRUCTION. 

The  complete  crank  shaft  is  now  ready  to  assemble  with 
the  other  parts.  To  do  this,  place  the  wheels  and  shaft  in 
position  on  the  bed  plate  and  insert  the  ends  of  the  shaft  into 
the  main  bearings,  which  are  slid  on  from  either  side  and 
fastened  into  position  by  the  cap  screws  in  their  bases.  The 
cylinder  and  supports  can  then  be  slid  onto  the  ends  of  the 
side  rods  and  secured  in  their  proper  places. 


Chapter  XV. 
CYLINDER    HEAD. 

CHUCK    PIECE.       TURNING  AND    FACING.       TURNING   OUTSIDE. 
DRILLING     FOR     SCREWS.       TRANSFERRING     HOLES     TO 
CYLINDER.      LOCATING  POSITIONS  OF  INLET  AND 
EXHAUST    VALVES.        BORING     FOR     EX- 
HAUST    VALVE.       BORING     FOR 
INLET   VALVE. 


CHAPTER  XV. 

THE   CYLINDER   HEAD. 

The  cylinder  head  has  a  chuck  piece  cast  on  the  outside, 
which  is  held  in  the  chuck  jaws  and  the  inside  of  the  head 
turned  first. 

The  shoulder  should  be  turned  down  to  make  a  snug  fit 
into  the  cylinder  tube.  Fig-  97  shows  the  head  in  the  lathe 
and  a  diamond  point  tool  in  the  slide  rest  to  cut  out  the  sharp 
corner  of  the  shoulder.  The  calipers  should  be  set  to  the 
proper  size  and  tried  as  shown. 

Turn  down  the  edge  of  the  head  to  a  diameter  of  3^-f- 
inches. 

Remove  from  the  chuck  and  reverse  the  head,  chucking 
it  by  the  outside  edge  or  the  shoulder  on  the  inside.  Cut 
off  the  chuck  piece  and  face  off  outside,  as  shown  in  Fig.  98. 

The  outside  should  be  faced  off  very  smooth  and  true. 
Mark  slight  indentation  in  center  of  head  while  it  is  revolv- 
ing in  the  lathe. 

When  finished,  remove  from  the  chuck  and,  with  the 
dividers,  set  at  iT9^-  inches,  using  the  indentation  as  a  center, 
mark  out  a  circle  on  which  to  space  holes  for  the  cap 
screws. 

Without  changing  the  setting  of  the  dividers  lay  off  on 
this  circle  six  points,  which  may  be  center-punched  for 
drilling. 

Drill  these  holes  with  a  No.  4  twist  drill  and,  when  the 


176 


GAS   ENGINE   CONSTRUCTION. 


CYLINDER   HEAD. 


177 


holes   have    been  transferred  to  the  cylinder,  they  can  be 
enlarged  to  J  inch. 

To  transfer  the  holes  to  the  cylinder  place  the  head  in 
position,  and  if  the  shoulder  has  been  made  a  tight  fit  in  the 
cylinder  tube  it  will  remain  in  position  while  the  holes  are 
being  drilled  in  the  cylinder  collar,  the  holes  in  the  head 
being  used  as  guide  holes  for  the  drill.  Should  the  shoulder 


FIG,  98, — FACING  OUTSIDE  OF  CYLINDER  HEAD, 

of  the  cylinder  head  fit  loosely  in  the  cylinder  tube  it  will 
be  necessary  to  hold  the  head  in  place  until  one  hole  has 
been  drilled  in  the  cylinder  collar.  This  hole  can  now  be 
tapped  J  inch,  20  threads,  the  corresponding  hole  in  the  head 
enlarged  to  4  inch,  and  the  head  can  then  be  fastened  on  with 
a  cap  screw  until  the  remaining  five  holes  have  been  drilled 
in  the  cylinder  collar. 

In  placing  the  cylinder  head  in  position  be  sure  to  have 


GAS   ENGINE   CONSTRUCTION. 

the  holes  come  in  the  positions  shown  in  Fig.  99  :  two  holes 
on  the  vertical  diameter  and  two  spaces  on  the  horizontal 
diameter. 

The  latter  are  required  for  the  inlet  and  exhaust  valves. 

Across  the  center  of  the  inside  of  the  head,  on  the  hori- 
zontal diameter,  a  line  can  be  scribed  and  the  center  of  the 
head  located  by  a  small  center-punch  mark. 


FIG.  99. — CYLINDER  HEAD. 


The  location  of  the  inlet  and  exhaust  valves  can  now  be 
laid  out  on  this  line. 

They  are  to  be  marked  by  a  center-punch  mark  J  J  inch 
each  side  of  the  center  point,  as  shown  in  Fig.  99.  The 
holes  in  the  head  are  bored  as  shown  in  Figs.  100  and  101. 

The  cylinder  head  must  be  clamped  on  the  face  plate 
with  distance  pieces  between  to  make  a  clearance  space  for 


CYLINDER   HEAD. 


I79 


i8o 


GAS   ENGINE   CONSTRUCTION. 


CYLINDER   HEAD.  •  l8l 

the  drill  and  boring-  tool  when  cutting  through  the  cylinder 
head. 

In  the  cuts  shown  three  pieces  of  -f-inch  hexagonal  brass 
rod  were  used.  A  small  bolt  was  passed  through  one  of  the 
cap  screw  holes  in  the  cylinder  head,  and  the  opposite  side 
was  held  by  a  small  adjustable  clamp,  as  shown. 

To  locate  the  head  at  the  proper  position  on  the  face 
plate,  bring  the  back  center  up  and  place  the  point  on  the 
center  punch  mark  of  the  center  of  the  hole  to  be  bored. 
The  head  can  be  firmly  held  against  the  face  plate  in  this 
manner  while  the  clamps  or  bolts  are  secured  in  place. 

When  the  head  is  clamped  in  position,  start  a  drill  at  the 
center  punch  mark  and,  after  drilling  through,  use  a  boring 
tool  in  the  slide  rest  to  finish  the  hole  and  true  it  up. 

Fig.  100  shows  the  boring  tool  in  position  and  the  hole  for 
the  exhaust  valve  finished. 

The  diameter  of  this  hole  should  be  ifa  inch. 

The  cylinder  head  is  now  to  be  loosened  and  clamped  in 
position  to  drill  and  bore  the  hole  for  the  inlet  valve. 

In  Fig.  101  It  will  be  seen  that  a  bolt  passes  through  the 
hole  drilled  for  the  exhaust  valve  with  washers  covering  the 
hole,  and  the  clamp  is  used  on  the  opposite  side  of  the 
head. 

This  hole  is  to  be  bored  and  finished  to  i  inch  diameter. 


Chapter  XVI. 
THE    INLET    VALVE. 

THE   CASING.      BORING  AND  FINISHING.      DRILLING   HOLE  FOR 
VALVE  STEM.      FINISHING  OUTSIDE.      TURNING  DOWN 
CHUCK  PIECE.      DRILLING  GAS  INLET  HOLES. 
DRILLING      AIR       PASSAGES.         THE 
VALVE.    TURNING  AND  FIT- 
TING    TO     VALVE 

SEAT. 

FITTING  STEEL  STEM.      GRINDING.      DRILLING   STEM    FOR   PIN. 

SPRING.      GAS  INLET  RING.      BORING  AND    RECESSING. 

DRILLING  FOR  STOP  COCK.     FILING  GROOVES. 

FINISHING      OUTSIDE      OF     RING. 

ASSEMBLING    THE 

PARTS. 


CHAPTER     XVI. 

INLET   VALVE. 

The  inlet  valve  castings  comprise  the  valve  casing,  gas 
inlet  ring,  and  valve. 

The  valve  casing  is  first  chucked  in  the  lathe  by  the  exten- 
sion on  the  back,  as  shown  in  Fig.  102. 

The  casing  is  centered  with  a  hand  tool  or  otherwise 
and  drilled  with  about  a  i-inch  drill  for  a  depth  of  f  J  inch. 

A  boring  tool  is  set  in  the  tool  post  of  the  lathe  and  the 
hole  bored  out  to  f  inch  diameter  for  a  depth  of  f  |-  inches. 

This  must  be  done  very  carefully  with  a  light  cut  to  finish 
smoothly. 

The  outer  end  is  now  to  be  faced  off  and  the  valve  seat 
beveled  to  an  angle  of  30°. 

The  next  operation  requires  some  care :  it  is  to  center  and 
drill  the  hole  for  the  guide  stem  of  the  valve.  Fig.  102 
shows  this  operation  clearly. 

The  centering  tool  is  placed  in  position  in  the  tool  post 
with  the  point  on  a  line  with  the  center  of  the  work. 

The  tool  is  now  fed  into  the  hole  of  the  valve  casing  until 
it  reaches  the  bottom. 

While  the  lathe  head  is  revolving,  it  is  fed  to  the  center 
of  the  casting,  and  if  the  point  of  the  tool  is  exactly  on  a 
line  with  the  center  of  the  work,  it  will  mark  an  indentation 
like  a  center-punch  mark.  Should  it  be  found  that  the  tool 
does  not  mark  at  the  center,  it  must  be  reset  until  it  makes 
the  indented  cut  exactly  in  the  center. 


186 


GAS   ENGINE   CONSTRUCTION, 


INLET   VALVE.  l8/ 

Be  very  careful  that  the  body  of  the  tool  does  not  touch 
the  finished  valve  seat  when  marking  the  center.  When 
the  center  is  marked  sufficiently  deep,  a  T3^--inch  twist  drill  is 
held  in  a  chuck  in  the  tail  stock  of  the  lathe  and  the  hole 
drilled  through  where  the  indentation  is  made. 

In  Fig.  102  the  center  marking  tool  is  shown  in  the  slide 
rest,  but  fed  back  out  of  the  way,  and  the  drill  is  in  position 
for  use.  When  the  guide  hole  has  been  drilled,  the  casing 
can  be  removed  from  the  chuck  and  the  outside  finished. 
Fig.  103  shows  this  operation.  A  short  piece  of  machine 
steel  or  iron,  slightly  larger  in  diameter  than  the  hole  in  the 
valve  casing,  is  gripped  in  the  chuck  and  the  end  turned 
down  until  the  casting  can  be  forced  on  by  hand. 

The  outside  of  the  body  of  the  casing  is  now  turned  down 
to  a  diameter  of  }|-  inch,  and  the  collar  on  the  valve  seat  end 
is  turned  down  to  make  a  driving  fit  into  the  smaller  of  the 
two  holes  bored  in  the  cylinder  head. 

A  shoulder  must  be  left  on  this,  as  shown  in  the  detail 
drawings,  to  prevent  the  valve  from  being  forced  through 
the  hole  in  the  cylinder  head  when  the  engine  is  working. 

The  outer  end  of  the  valve  casing,  which  has  been  drilled 
for  the  valve  stem,  is  turned  down  to  a  diameter  of  -j8ff  inch 
and  the  end  of  the  casing  cut  off,  leaving  the  stem  a  length 
of  -fa  inch,  as  shown  in  the  detail  drawings.  In  Fig.  103  the 
the  casing  is  shown  on  the  mandrel  and  finished,  with  the 
exception  of  turning  off  the  superfluous  length. 

The  lathe  tool  is  in  position  for  this  last  operation.  The 
casing  is  removed  from  the  mandrel  when  finished. 

The  next  procedure  is  to  drill  the  casing  for  the  gas  inlet 
holes.  These  holes  must  be  carefully  center-punched  in  the 
center  of  the  valve  seat.  Nine  holes  are  required,  and  the 
size  of  the  drill  is  No.  45.  These  holes  must  start  at  the 
center  of  the  gas  ring  and  come  through  to  the  outside  of 


188 


GAS   ENGINE   CONSTRUCTION. 


INLET  VALVE.         ;         f  189 

the  casing  below  the  collar  which  is  turned  on  the  casing 
to  fit  the  hole  in  the  cylinder  head,  as  shown  in  the  detail 
drawings.  The  casing  must  be  held  in  such  a  manner  that 
the  drill  will  run  in  the  required  direction. 

The  lower  end  of  the  valve  casing  must  be  drilled  for  air 
passages.  Drill  four  equidistant  holes  with  a  -|-inch  drill  as 
close  to  the  lower  guide  stem  as  the  drill  can  be  held. 
Enlarge  these  holes  with  a  small  square  file  until  four  ribs 
Y^inch  wide  are  left  to  support  the  guide  stem. 

Fig.  104  shows  the  appearance  of  the  casing  when  the 
holes  are  enlarged,  as  described. 

The  valve  proper  is  a  small  casting  having  four  thin 
wings  to  guide  it  in  the  casing,  aside  from  the  steel  rod 
which  passes  through  the  guide  stem  of  the  casing. 

The  four  wings  are  cast  on  one  side  of  the  circular  valve, 
and  on  the  opposite  side  is  cast  a  small  chuck  piece  by 
which  it  is  held  in  the  jaws  of  the  chuck  while  being 
finished. 

Fig.  105  shows  the  valve  in  the  lathe. 

First,  the  four  wings  are  turned  down  until  they  fit  easily 
into  the  hole  bored  in  the  casing. 

The  valve  proper  is  then  turned  down  to  size  and 
beveled  to  fit  the  bevel  of  the  valve  seat  in  the  casing. 

The  hub  where  the  four  wings  come  together  is  next  cen- 
tered carefully  and  a  hole  drilled  to  the  depth  of  -fo  inch. 
In  Fig.  105  these  operations  are  clearly  shown.  The  valve 
casing  is  lying  on  the  slide  rest  in  position  to  show  the  inte- 
rior, and  the  valve  is  turned  to  the  proper  size  with  the  drill 
in  position  to  make  the  hole  for  the  steel  valve  stem. 

The  stem  must  be  a  good  fit,  and  in  drilling  the  hole  for  it 
be  sure  that  the  drill  starts  right,  else  the  valve  stem  will  not 
be  concentric  with  the  valve,  and  it  will  require  a  large 
amount  of  grinding  to  make  the  parts  a  good  fit.  The  valve 


190 


GAS   ENGINE   CONSTRUCTION. 


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INLET  VALVE.  f  191 

can  now   be  cut  from  the  chuck  piece  with  a  cut-off  tool, 
held  in  the  slide  rest,  and  the  stem  inserted. 

The  next  operation  is  to  grind  the  valve  on  the  valve  seat. 
To  do  this,  place  the  valve  and  stem  in  position  in  the  cas- 
ing and  grip  the  lower  end  of  the  valve  stem  in  the  jaws  of 
the  chuck.  Place  a  little  fine  emery,  mixed  with  oil,  on  the 
valve  seat  and  start  the  lathe  head  running  at  the  fastest 
speed. 

Press  the  casing  against  the  valve  while  rotating. 

Put  on  a  little  oil  without  emery,  with  the  valve  still  rotat- 
ing. Remove  from  the  chuck  and  carefully  wipe  off  all 
emery  and  oil,  and  test  the  valve  by  suction  on  the  lower 
end  of  the  casing.  If  not  tight,  repeat  the  grinding  process 
until  the  desired  result  is  obtained. 

The  stem  must  be  drilled  very  near  the  end  for  a  small 
pin,  against  which  the  washer  and  spring  press  to  close  the 
valve 

The  spring  is  made  of  No.  24  steel  wire  and  should  be 
only  of  sufficient  strength  to  close  the  valve  by  overcoming 
the  friction  of  the  stem  and  wings.  This  will  allow  the  valve 
to  open  at  once  as  soon  as  the  piston  begins  its  forward 
stroke  without  a  pressure  in  the  cylinder. 

The  gas  inlet  ring  is  held  in  the  chuck,  as  shown  in  Fig. 
106,  but  it  must  have  clearance  enough  at  the  back  to  pre- 
vent the  boring  tool  from  cutting  into  the  chuck  when  it 
passes  through  the  ring. 

Bore  out  the  ring  until  it  would  make  a  tight  driving  fit 
on  the  valve  casing.  Next  bore  out  a  recess  in  the  ring 
J  inch  deep  and  f  inch  in  width,  after  which  the  front  of  the 
ring  is  faced  up. 

In  this  cut  the  ring  is  shown  with  the  inside  bored  to  fit 
the  diameter  of  the  casing,  the  recess  turned  out,  and  the. 
ring  faced  up  on  the  front. 


I92 


GAS   ENGINE   CONSTRUCTION. 


INLET  VALVE. 


193 


194  GAS   ENGINE   CONSTRUCTION. 

The  ring  can  then  be  removed  from  the  chuck  and  placed 
on  the  angle  plate,  as  shown  in  Fig.  107,  where  the  stem  is 
to  be  drilled  out  and  the  outside  finished.  In  this  cut  the 
operations  have  been  finished,  but  the  locations  of  the  tools 
therein  are  sufficient  without  a  lengthy  description. 

The  ring  in  this  case  was  clamped  down  around  the  pin  of 
the  angle  plate  and  a  piece  of  brass  tubing  was  used  to 
build  up  to  the  clamping  washer  on  top.  The  hole  should 
be  T5B  inch  in  diameter  and  tapped  out  for  a  -J-inch  stopcock, 
iron  pipe  size. 

On  the  side  of  the  ring  which  was  faced  up  when  held  in 
the  chuck  a  number  of  half-round  grooves  are  to  be  filed,  as 
shown  in  the  detail  drawings. 

These  grooves  are  for  the  gas  to  pass  through  from  the 
recess  in  the  ring  to  the  chamber  formed  between  the  hole 
in  the  cylinder  head  and  the  valve  casing,  which  is  clearly 
shown  in  the  detail  drawings. 

Should  the  operator  possess  a  screw-cutting  lathe,  this 
part  which  is  grooved  may  be  entirely  cut  away  while  the 
ring  is  in  the  chuck  and  a  fine  thread  cut  in  the  remaining 
ring.  The  casing  can  be  threaded  on  the  lower  end  to  cor- 
respond, while  in  the  position  shown  in  Fig.  103. 

The  outside  of  the  ring  can  be  finished  up  by  filing  and 
polishing  with  emery  cjoth. 

The  gas  ring  should  have  three  lugs  cast  on  the  circum- 
ference, as  shown  in  the  detail  drawings,  Fig.  108.  These 
were  not  placed  on  the  parts  photographed.  Through 
these  lugs  holes  are  drilled  for  screws  to  attach  the  ring 
firmly  to  the  cylinder  head.  It  was  found  that  adjusting- 
the  amount  of  gas  admitted  by  opening  and  closing  the 
stopcock  below  had  a  tendency  to  loosen  the  ring  on  the 
casing  of  the  inlet  valve. 

The  inlet  valve  should  not  be  put  into  the   cylinder  head 


INLET  VALVE. 


195 


GAS   ENGINE   CONSTRUCTION. 


INLET   VALVE. 


I97 


until  the  exhaust  valve  and  igniter  have  been  finished  and 
fitted. 

In  putting  the  inlet  valve  together  in  the  cylinder  head, 
first  put  a  very  little  white  lead  on  the  collar  of  the  valve 
casing  to  make  a  perfectly  tight  joint  when  the  casing  is 
forced  into  place. 

It  is  best  to  force  this  part  into  place  by  pressure.  This 
can  be  easily  done  in  the  vise,  provided  the  parts  are  pro- 
tected by  blocks  of  wood.  After  the  casing  is  in,  place  a 


FIG.  109. — CYLINDER  HEAD,  INLET  AND  EXHAUST  VALVE  PARTS. 

very  small  amount  of  white  lead  around  the  hole  in  the  cyl- 
inder head  where  the  gas  ring  is  to  fit  against  it. 

Now  force  the  ring  onto  the  casing  and  tight  up  against 
the  cylinder  head  with  the  stem  pointing  downward.  It 
may  be  advisable  to  screw  in  the  stopcock  before  the  ring  is 
forced  into  position. 

Fig.  109  shows  the  parts  of  the  inlet  valve,  exhaust  valve, 
and  cylinder  head  before  fitting  and  assembling. 


Chapter  XVII. 
EXHAUST   VALVE. 


CHUCKING    THE    CASING.       BORING    AND     FINISHING    INSIDE. 
VALVE   SEAT.      CENTERING  AND  DRILLING   HOLE   FOR 
VALVE   STEM.      BORING   FOR   EXHAUST   PIPE. 
THE  VALVE.      TURNING  AND  DRILL- 
ING.       GRINDING.        CUT- 
TING OFF  CHUCK 

PIECE. 

DRILLING    VALVE    LEVER    BRACKET.       DRILLING    FOR    SCREW 
HOLES.       THE    SPRING.       HARDENING   'AND    TEMPER- 
ING.      VALVE    LEVER.       DRILLING    AND    FIT- 
•  TING.      HARDENED  STEEL  PIN.      AT- 
TACHING    TO     CYLINDER 
HEAD. 


CHAPTER  XVII. 

EXHAUST   VALVE. 

The  exhaust  valve  proper  is  composed  of  three  pieces,  the 
casing,  valve  and  valve  stem. 

In  the  exhaust  valve  casing,  as  in  the  inlet  valve  casing, 
we  shall  suppose  it  has  been  cast  solid. 

The  casing  is  first  gripped  in  the  jaws  of  the  chuck  by  the 
extension  of  the  valve  stem  guide  on  the  back  of  the  cast- 
ing. Fig.  1 10  shows  the  casing  chucked. 

The  body  of  the  casing,  up  to  the  flange,  is  to  be  turned 
down  to  a  diameter  of  i-^  inches,  to  fit  the  hole  bored  in  the 
cylinder  head,  and  the  flange  must  be  faced  up  square  with 
the  body.  Center  and  bore  out  the  interior  of  the  casing  to 
a  diameter  of  f  inch,  as  shown  in  the  detail  drawings. 

Bevel  the  valve  seat  to  an  angle  of  30°. 

With  the  centering  tool  mark  the  bottom  of  the  hole  with 
an  indentation  in  which  to  drill  the  hole  for  the  valve  stem 
guide.  Use  a  J-inch  drill  for  this  hole  and  be  sure  that  it 
starts  true. 

The  next  operation  to  the  casing  is  to  bore  the  hole  for 
the  exhaust  pipe  on  the  side  of  the  body.  This  procedure 
is  clearly  shown  in  Fig.  in.  The  casing  is  mounted  on  the 
angle  plate  and  the  angle  plate  pin  is  inserted  from  below 
the  shelf  and  prevented  from  coming  up  through  by  a  washer 
and  a  piece  of  brass  tubing. 

The  J-inch  cap  screw  is  now  put  down  through  the  hole 


202 


GAS   ENGINE   CONSTRUCTION. 


I 


EXHAUST   VALVE. 


203 


I* 

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f    % 

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204  GAS   ENGINE   CONSTRUCTION. 

forming  the  valve  stem  guide  and  thus  clamps  the  valve  cas- 
ing down  firmly  onto  the  shelf  of  the  angle  plate. 

The  angle  plate  must  now  be  set  with  the  boss  on  the 
side  of  the  casing  on  a  line  with  the  center  of  the  lathe 
spindle. 

Center  the  boss  with  the  centering  tool,  and  drill  and  bore 
to  %  inch  to  fit  a  piece  of  -J-inch  brass  tubing. 

The  valve  is  a  casting  of  the  same  shape  and  style  of  the 
inlet  valve,  with  the  exception  that  it  is  a  little  larger. 

The  valve  is  turned  and  drilled  in  the  same  manner  as 
shown  in  Fig.  105. 

The  valve  stem  is  made  of  a  piece  of  J-inch  steel  rod. 

In  Fig.  1 12  is  shown  another  method  of  grinding  the  valve 
on  its  seat.  This  differs  from  the  directions  given  for  grind- 
ing the  inlet  valve,  as  in  this  case  the  valve  is  ground  on  the 
valve  seat  before  being  cut  off  from  the  chuck  piece. 

This  method  is  not  as  accurate  as  that  described  for  the 
inlet  valve,  as  it  does  not  allow  for  any  variation  which  may 
come  from  either  the  hole  drilled  in  the  valve  for  the  stem, 
or  the  hole  in  the  casing  for  the  guide  being  out  of  true. 
We  consider  the  first  method  the  more  accurate,  but  a  modi- 
fication of  both  will  be  found  as  accurate,  which  is  to  drill 
the  valve  to  receive  the  stem  and  force  the  stem  into  position, 
by  using  the  back  center ;  but  care  must  be  exercised  not  to 
disturb  the  setting  of  the  valve  in  the  chuck.  When  the 
valve  stem  is  in  place  the  casing  may  be  held  in  position  by 
the  hand,  as  shown  in  Fig.  112,  but  without  the  back  center. 
The  valve  can  then  be  accurately  ground,  with  emery  and 
oil,  as  described  for  the  inlet  valve. 

In  grinding  the  valve  do  not  let  the  emery  get  down  into- 
the  body  of  the  casing  to  grind  the  wings  and  valve  stern. 

After  the  valve  is  ground  in  this  manner  a  cut-off  tool  can 
be  used  in  the  slide  rest  to  cut  off  the  chuck  piece  on  the 


EXHAUST  VALVE. 


205 


206 


GAS    ENGINE   CONSTRUCTION. 


EXHAUST    VALVE. 


207 


back  of  the  valve.  Fig.  109  shows  the  valve,  valve  stem  and 
casing  put  together  at  this  stage  of  the  operation. 

The  chuck  piece  on  the  end  of  the  casing  can  now  be  cut 
down  to  the  size  given  in  the  detail  drawings. 

The  boss  on  the  end  of  the  valve  lever  bracket  is  center- 


FIG.  114. — EXHAUST  VALVE  IN  POSITION  FOR 
DRILLING  SCREW  HOLES. 

punched  and  a  -J  inch  hole  drilled  and  reamed  in  it.  This  is 
for  the  steel  shaft  of  the  valve  lever. 

The  clearance  holes  for  the  screws  by  which  the  complete 
valve  is  secured  to  the  cylinder  head  are  next  to  be  drilled. 

The  holes  are  laid  out  and  center-punched  in  the  four  pro- 


;208  GAS    ENGINE   CONSTRUCTION. 

jections  of  the  flange  of  the  casing.  Fig.  1 14  shows  how  the 
casing  is  held  for  drilling,  by  clamping  the  bracket  on  the 
shelf  of  the  angle  plate  with  a  ^-inch  cap  screw  passing 
through  the  hole  for  the  valve  lever  shaft. 

The  end  of  the  valve  stem  should  be  cut  down  to  the 
dimensions  shown  in  the  drawings,  but  the  groove  for  the 
spring  should  be  first  cut  in  the  stem.  The  spring  is  cut 
from  a  piece  of  sheet  steel  the  shape  and  size  given  in  the 
detail  drawings.  The  steel  from  an  ordinary  clock  spring 
will  be  found  to  be  about  the  right  thickness.  If  the  sheet 
steel  is  not  soft  enough  to  bend,  it  should  be  annealed  by 
heating  to  a  dull  red  and  allowing  it  to  cool  slowly  in  the 
air.  Bend  the  spring  to  the  shape  shown,  after  which  it 
must  be  hardened  and  tempered. 

Place  some  machine  oil  in  a  small  cup  or  other  dish  suf- 
ficient to  immerse  the  entire  spring.  First  heat  the  spring 
evenly  to  a  cherry  red  and  plunge  it  into  the  bath  of  cold 
oil.  The  spring  will  then  be  hard  and  as  brittle  as  a  piece 
of  glass,  therefore  do  not  attempt  to  bend  it  when  it  is 
removed  from  the  oil.  The  spring  must  now  be  tempered. 

The  best  method  of  doing  this  is  to  have  a  piece  of  wire, 
long  enough  to  hold  in  the  hand,  and  hook  one  end  of  it 
into  the  hole  in  the  end  of  the  spring. 

Lift  the  spring  from  the  oil  bath  and,  without  shaking  off 
the  oil  which  will  cling  to  it,  place  the  spring  in  the  flame 
until  the  oil  catches  fire.  Hold  up  from  the  flame  and  let 
the  oil  burn  off  until  the  flame  dies  out,  then  plunge  the 
spring  into  the  oil  bath  again.  Repeat  this  operation  until 
the  oil  has  been  burned  off  three  times,  and  if  the  material 
used  was  of  good  quality  the  spring  will  be  of  the  proper 
temper. 

This  spring  must  be  of  sufficient  strength  to  prevent  the 
exhaust  valve  from  opening  by  the  suction  of  the  piston. 


EXHAUST    VALVE. 


209 


The    spring   is  kept  in   position    by  the  small  pin  passing 
through  it  just  above  the  hole  cut  for  the  valve  stem. 

The  valve  lever  has  a  hole  drilled  through  the  center  boss 
in  which  the  J-inch  steel  pin  must  fit  tight.  Should  it  be 
found  that  the  hole  is  a  trifle  large  for  a  driving  fit,  the  lever 
and  pin  must  be  drilled  through  from  the  side  and  a  small 
pin  driven  in  to  fasten  them  together. 


BRASS 

MAKE  ONE 


FIG.  115. — EXHAUST  VALVE  LEVER. 

The  pin  extends  down  flush  with  the  bottom  of  the  boss 
on  the  bracket  and  has  a  hole  drilled  and  tapped  in  the  lower 
end  for  a  No.  4-36  machine  screw.  A  small  washer  about 
£  inch  in  diameter,  clamped  onto  the  end  of  the  pin  by  the 
screw,  prevents  it  from  being  lifted  out  of  the  bracket. 


2IO 


GAS   ENGINE   CONSTRUCTION. 


SCALE  TWICE  SIZE 

FIG.  116. — HARDENED 

STEEL   PIN   IN   EXHAUST 

VALVE  LEVER. 


In  the  outer  end  of  the  lever  a  hole  is  drilled  and  tapped 
for  a  No.  8-32  machine  screw.  This  allows  an  adjustment 
in  setting  the  valve  rod  gearing  to  open  und  close  the  valve 
at  the  proper  time. 

If  the  engine  is  to  have  a  governor,  a  small  hardened  steel 

pin  must  be  set  into  the  end  of  the 
lever  for  the  governor  pin  to  catch 
in. 

This  mechanism  will  be  described 
under  the  head  of  governor  in  an- 
other chapter. 

When  the  exhaust  valve  is  com- 
pleted it  should  be  placed  on  the 
cylinder  head  of  the  engine  in  such  a  position  that  the 
adjusting  screw  of  the  valve  lever  is  on  a  line  with  the 
valve  rod  on  the  side  of  the  cylinder. 

As  the  flat  steel  spring  shown  in  Fig.  113  is  somewhat 
difficult  to  make,  the  builder  can  substitute  a  spring  of  steel 

piano  wire  No.  18  (Brown  & 
Sharpe  gauge)  coiled,  as 
shown  in  Fig.  1 16  A. 

A  piece  about  six  inches  in 
length  is  sufficient  to  make 
the  spring.  The  wire  must  be 
coiled  around  a  mandrel  con- 
siderably smaller  than  the  size 
of  the  loop  shown  in  the  cut, 
as  piano  wire  is  very  elastic. 
One  end  of  the  wire  spring 
is  bent  into  a  loop  to  fit  the 
groove  turned  in  the  valve  stem.  The  other  end  of  the 
spring  is  bent  at  a  right  angle  and  inserted  in  a  small  hole 
drilled  in  the  casing  of  the  valve,  just  below  the  valve  stem, 
as  shown  in  the  cut.  Do  not  make  this  bend  too  abrupt  or 
the  wire  may  break. 


FIG. 


A. — STEEL  WIRE 
SPRING. 


Chapter  XVIII. 
VALVE     GEARING. 

GEAR  WHEELS.       FINISHING   GEARS.      CRANK   PIN   FOR  VALVE 
RODS.      CONNECTING  ROD.      KNUCKLE  JOINT.     VALVE 
ROD     GUIDES.        DRILLING     CYLINDER     COL- 
LARS    FOR     GUIDES.        ADJUSTING 
THE   VALVE   ROD. 


CHAPTER    XVIII. 


VALVE      GEARING. 

In  an  engine  of  this  style  the  cycle  is  completed  in  two 
revolutions. 

To  accomplish  this,  the  valve  rod  must  be  geared  to  open 
the  exhaust  valve  once  in  two  revolutions  of  the  engine. 

This  is  done  by  placing  a  gear  wheel  of  i  inch  pitch 
diameter  on  the  shaft  of  the  engine  and  another  gear  of  2 
inch  pitch  diameter  on  the  gear  stud  of  the  main  bearing. 

The  gears  should  be  finished  bright,  and  to  do  this  neatly 
they  should  be  held  in  the  chuck,  as  shown  in  Fig.  117. 


FIG.  117. — FACING  GEAR  WHEEL. 


214 


GAS   ENGINE   CONSTRUCTION. 


A  small  piece  of  narrow  strip  brass  or  spring  steel  is 
placed  around  the  outside  of  the  gear  teeth.  This  protects 
the  teeth  from  the  jaws  of  the  chuck  and  allows  the  hub  and 
web  of  the  gear  to  be  finished. 

After  finishing  one  side,  the  gear  can  be  turned  over  and 
the  other  side  finished. 

A  steel  crank  pin  is  set  into  the  larger  gear  wheel,  the 
center  of  the  hole  for  the  crank  pin  being  £J  inch  from  the 
center  of  the  hole  in  the  hub.  This  gives  the  connecting 
rod  and  valve  rod  a  stroke  of  ij1^  inches. 

The  crank  pin  is  made  a  driving  fit  in  the   gear  wheel. 


FOR  TAPERED  PIN 


PITCH  DIA.  =  1* 
NO.    OF  TEETH  2* 


FIG.  118. — GEAR  WHEELS. 

The  outer  end  is  drilled  and  tapped  for  a  No.  4-36  machine 
screw,  by  which  a  small  washer  is  clamped  on  the  end  of 
the  crank  pin  to  keep  the  connecting  rod  in  place. 

The  end  of  the  connecting  rod,  where  it  is  attached  to  the 
crank  pin,  is  made  from  a  piece  of  sawed  brass  f  byT9Finch. 
in  size  and  2-J-  inches  long.  One  end  is  drilled  with  a  J  inch 
hole  for  the  crank  pin  and  the  other  is  drilled  lengthwise 
with  a  J-inch  drill  for  a  depth  of  ij  inches.  The  outside  of 
this  end  is  turned  down  to  a  diameter  of  f  inch. 

The  connection  between  the  valve  rod  and  the  connecting 
rod  is  by  a  knuckle  joint. 

The  bearings  for  the  valve  rod  are  secured  to  the  lugs  on 


VALVE    GEARING, 


215 


the  side  of  the  cylinder  collars.  The  hole£  for  the  J-inch 
steel  valve  rod  are  first  drilled  in  each  guide  and  they  are 
then  fitted  to  the  lugs  by  filing. 

The  screw  holes  are  then  drilled  in  the  guides,  and,  after 
fitting,  they    are   transferred    to 
the  cylinder  collars. 

The  cylinder  will  need  to  be 
removed  from  the  frame  for 
drilling  these  holes. 

The  connecting  rod  must  be 
offset  to  bring  it  in  line  with  the 
valve  rod.  This  is  clearly  shown 
in  the  detail  drawings. 

The  dimensions  of  the  differ- 
ent parts  of  the  valve  gearing 
are  also  shown. 

The  knuckle  joint  is  made 
from  two  pieces  of  f-inch  square 
brass  rod.  One  piece  is  cut 
away  in  the  center  and  the  other 
cut  away  on  each  side  to  form 
the  joint.  In  securing  the 
knuckle  joint  to  the  valve  rod, 
it  is  best  to  drill  through  both 
parts  and  use  a  small  wire  pin. 
This  allows  the  parts  to  be  dis- 
connected easily. 

The  other  end  of  the  knuckle 
joint  can  be  secured  to  the  connecting  rod  by  soldering. 

The  crank  pin  end  of  the  connecting  rod  should  not  be 
pinned  permanently  until  the  adjustment  is  found  to  be 
right,  when  the  pin  can  be  cut  off  flush  with  the  sleeve  and 
riveted  in  place. 


216 


GAS   ENGINE   CONSTRUCTION. 


To  adjust  the  valve  rod  to  open  the  exhaust  valve  at  the 
proper  time,  it  will  be  found  necessary  to  uncouple  the  valve 
rod  from  the  knuckle  joint  and  remove  the  screw  from  the 
gear  stud.  The  gear  wheel  can  then  be  removed  and 


FlG.    120. 


rotated  forward  or  back  as  needed  to  operate  the  valve  at 
the  proper  moment. 

When  the  point  is  found,  a  scratch  should  be  made  across 
a  tooth  of  the  small  gear  and  the  space  of  the  large   one 


-V 

*! 

OR]  TAPER  ED  PIN 

r*-^  =     = 

rj 

MAKE  ONE 

FIG.  121. — VALVE  ROD. 


which  engages  with  it.  This  is  for  the  purpose  of  placing 
the  gears  together  in  their  exact  relative  positions  should  it 
become  necessary  to  again  separate  them. 

Fig.  121  shows  the  steel  valve  rod.  The  indentation  for 
the  governor  roller  is  clearly  shown.  The  measurements 
given  in  this  cut  of  the  distance  from  the  end  of  the  rod  to 
the  indentation  should  not  be  strictly  adhered  to.  This 
indentation  should  not  be  made  until  the  governor  is  com- 
pleted and  in  place,  as  described  in  Chapter  XIX. 


Chapter  XIX. 
GOVERNOR. 


DESCRIPTION    OF    GOVERNOR.       SPRING.       GOVERNOR    LEVER. 

WEIGHT.       THUMB    SCREW.        NOTCH    IN    VALVE 

ROD.      STEEL   ROLLER.      CLUTCH 

PINS. 


CHAPTER  XIX. 

GOVERNOR. 

The  governor  shown  in  connection  with  this  engine  was 
designed  by  the  authors  and  will  be  found  to  work  very 
satisfactorily.  This  governor  belongs  to  the  class  called 
inertia  governors. 

The  detail  drawings  show  clearly  the  construction  of  the 
different  parts  and  Figs.  122  and  123  are  to  show  the  opera- 
tion of  the  governor.  In  the  cuts  A  represents  the  valve 
rod  and  B  is  the  end  view  of  the  exhaust  valve  lever.  C  is 
a  small  hardened  steel  pin  having  a  groove  turned  around 
the  top  end.  This  pin  fits  into  a  hole  drilled  in  the  end  of 
the  exhaust  valve  lever. 

D  is  the  end  of  the  bracket  attached  to  the  exhaust  valve 
to  support  the  lever.  E  is  the  valve  rod  bearing,  through 
the  lugs  of  which  passes  a  screw  forming  the  bearing  for 
the  moving  parts  of  the  governor. 

Fis  the  governor  lever,  having  a  weight  G  at  its  outer 
end.  On  the  side  of  the  lever  is  a  projection,  into  which  is 
fitted  the  hardened  steel  pin  H  having  a  notch  formed  on 
the  side.  This  notch  engages  the  groove  formed  in  the  pin 
C,  if  the  speed  of  the  engine  is  too  great. 

Along  the  underside  of  the  governor  lever  is  a  flat  steel 
spring  7.  This  spring  is  attached  to  the  lever  just  behind 
the  pin  //"and  extends  forward  far  enough  to  allow  the  lower 
end  of  the  thumb  screw  J  to  rest  on  its  free  end. 


22O 


GAS   ENGINE   CONSTRUCTION. 


K  is  one  of  two  parallel  pieces  of  brass,  between  which 
the  spring  /  is  free  to  move.  Between  the  outer  ends  of 
these  pieces  is  placed  a  distance  piece  L  and  below  this  is  a 
steel  roller  37,  which  turns  freely  on  the  small  steel  pin 
shown.  On  the  upper  side  of  the  steel  valve  rod  A  is  filed 
a  small  depression,  clearly  shown  in  Fig.  121.  This  depres- 


FIG.  122. — GOVERNOR. 


FIG.  123. — GOVERNOR. 

sion  should  not  be  filed,  however,  until  all  the  other  parts 
of  the  governor  have  been  completed  and  put  in  place. 

The  action  of  the  governor  is  simple  and  effective.  In 
Fig.  123  is  shown  the  parts  in  their  respective  positions  when 
the  piston  of  the  engine  is  traveling  forward  under  the  im- 
pulse of  an  explosion  of  the  charge  in  the  cylinder.  The 
valve  rod  A  will  then  be  moving  in  the  direction  of  the 


GOVERNOR.  .,  j  221 

arrow  shown  below  it.  The  exhaust  valve  is  closed  and  the 
exhaust  valve  lever  B  is  in  the  position  shown. 

The  depression  in  the  valve  rod  is  seen  just  to  the  left  of 
the  valve  rod  bearing-  E.  The  hardened  steel  pin  H  is 
directly  over  the  pin  C. 

On  examining  the  relative  positions  of  the  parts  in  Fig. 
122  it  will  be  seen  that  the  valve  rod  A  has  reached  the  end 
of  its  travel,  the  roller  M  has  entered  the  depression  filed  in 
the  top  of  the  valve  rod,  and  in  consequence  the  lever  F  and 
weight  £are  lowered.  The  notch  of  the  pin  H  is  now  lower 
than  the  top  of  the  pin  C. 

As  the  weight  of  the  lever  /'and  weight  G  is  carried  by 
the  spring-  /,  resting  on  the  distance  pin  /,  it  will  be  seen 
that  if  the  spring  is  under  sufficient  tension  the  lever  F  will 
rise  at  once  as  the  valve  rod  A  moves  forward  and  the  roller 
M  emerges  from  the  depression.  In  this  case  the  pin //"will 
just  clear  the  top  of  the  pin  C  and  the  governor  valve  will 
close.  If,  however,  the  valve  rod  moves  forward  too  swiftly, 
the  spring  /will  bend  before  the  weight  £and  lever  F  move 
upward,  in  which  case  the  pin  //"will  engage  the  pin  C,  thus 
holding  the  exhaust  valve  open. 

In  this  instance,  as  the  piston  travels  forward  on  the 
beginning  of  a  new  cycle,  a  fresh  charge  of  gas  and  air  will 
not  be  drawn  into  the  cylinder  and  the  engine  will  complete 
a  cycle  running  free,  without  admission,  compression  or 
explosion,  until  the  valve  rod  A  again  reaches  the  exhaust 
valve  lever  B,  when  the  two  pins  C  and  /Twill  be  disengaged 
and  be  again  in  the  position  shown  in  Fig.  122.  As  the  valve 
rod  travels  forward  again,  if  the  speed  of  the  engine  has 
decreased  to  normal,  the  pins  will  pass  each  other  and  the 
exhaust  valve  close.  If  the  speed  of  the  engine  is  too  great, 
however,  the  pins  will  engage  as  before  and  the  engine  miss 
another  cycle. 


222 


GAS   ENGINE   CONSTRUCTION. 


The  tension  of  the  spring  can  be  changed  while  the  engine 
is  in  motion  by  the  thumb  screw  J. 

Screwing  the  thumbscrew  down  will  increase  the  speed 
of  the  engine.  In  adjusting  the  governor  the  weight  G  can 
be  moved  in  or  out  on  the  lever  until  the  proper  position  is 
reached. 

In  constructing  the  different  parts  of  the  governor  little 


*4-32  SCREW 


OLL  LOOSE  ON 

TEELP1N 


FIG.  124.  —  GOVERNOR. 

difficulty  will  be  found.  The  governor  lever  is  filed  up  at 
the  forward  end  and  the  back  end  can  be  turned  down  to 
fit  the  hole  drilled  in  the  weight.  The  two  parallel  pieces 
should  be  firmly  clamped  or  soldered  together  until  the 
three  holes  have  been  drilled  through  both  pieces. 

The  screw  which  holds  the  governor  in  position  on  the 
valve  rod  bearing  passes  through  two  separate  projections 
of  the  governor  lever.  This  is  to  give  the  lever  enough 


GOVERNOR.  22J 

bearing  on  the  screw  to  prevent  any  side  motion  of  the 
lever. 

The  thumb  screw  can  be  turned  from  a  piece  of  brass  rod. 
When  threading  it,  have  the  die  open  slightly  and  cut  the 
thread  a  good  full  size,  as  it  must  fit  tightly  in  the  hole 
tapped  for  it  in  the  governor  lever  to  prevent  the  screw  from 
turning  by  the  jar  of  the  engine  when  running. 

A  governor  could  be  made  of  fewer  pieces  than  this  one, 
which  would  work  on  the  centrifugal  principle,  the  same  as 
the  ordinary  steam  engine  governor,  but  we  do  not  consider 
that  as  reliable  as  the  one  here  shown  unless  it  is  driven  by 
gearing  it  directly  to  the  shaft. 

If  it  is  run  with  a  belt  the  engine  will  "  run  away  "  if 
the  belt  breaks.  It  would  require  an  extra  attachment  to 
prevent  this. 

Another  great  advantage  in  the  governor  here  shown  is 
that  the  speed  of  the  engine  can  be  varied  at  will  by  turning 
the  adjusting  thumb  screw. 

This  can  be  done  while  the  engine  is  in  motion  and  will 
be  found  of  great  advantage  in  laboratory  work  where  the 
speed  of  machines  and  models  can  be  varied  to  suit  the 
requirements. 

The  only  part  of  this  governor  which  is  at  all  liable  to 
break  is  the  spring,  and  this  would  at  once  stop  the  engine, 
as  the  support  of  the  governor  lever  would,  in  that  case,  be 
removed  and  there  would  be  nothing  to  hold  the  catch  pins 
apart. 

Should  the  weight  become  loose  and  slip  off  the  end  of 
the  lever  the  engine  would  "  run  away,"  but  this  could  not 
happen  under  ordinary  circumstances.  When  the  proper 
position  of  the  weight  is  found  the  set  screw  should  be 
removed  from  the  weight,  and  a  scriber  introduced  through 
the  screw  hole  to  mark  the  point  on  the  lever  that  the  screw 


224  GAS   ENGINE   CONSTRUCTION. 

touches.  A  small  indentation  can  be  made  with  a  drill  at 
this  point  for  the  end  of  the  screw  to  enter,  which  will  pre- 
vent its  sliding  out  of  place. 

If  one  wishes  to  leave  the  weight  free  to  be  moved  along 
the  lever  and  clamp  it  wherever  desired,  it  is  advisable  to 
drill  and  tap  a  hole  for  a  No.  4-36  machine  screw  in  the  end 
of  the  lever  and  fasten  a  brass  washer  in  this  manner.  The 
washer  should  be  about  T5^-  or  f  inch  in  diameter. 

Another  effective  way  would  be  to  drill  a  small  hole 
through  the  lever  near  the  end  and  drive  in  a  small  pin 
which  would  project  on  both  sides.  Either  method  will 
keep  the  weight  on  the  lever  and  prevent  a  possible  acci- 
dent. 


Chapter  XX. 
IGNITER. 

PLATINUM    POINTS.      INSULATION.      FIBER    PROTECTORS.      CE- 
MENTING   IGNITER    TO    TIPS.       ATTACHING   TO   CYLINDER 
HEAD.       BENDING    PLATINUM    POINTS.       THE    SPARK. 
ELECTRICAL   CONNECTIONS.       BATTERY.       SPARK 
COIL.        CONTACT     POINTS.        FIBER     BLOCK. 
FIBER     PIN     IN     GEAR    WHEEL     HUB. 
CHANGING    THE     MOMENT     OF 
CONTACT. 


CHAPTER  XX. 

IGNITER   AND    ELECTRICAL   CONNECTIONS. 

The  igniter  in  this  engine  is  composed  of  two  brass  wires 
threaded  at  the  outer  extremities  for  clamping  the  wires 
from  the  secondary  terminals  of  a  spark  coil,  and  the  inner 
ends  are  extended  by  pieces  of  platinum  wire,  which  almost 
meet  inside  the  cylinder  head. 

These  wires  must  be  insulated  from  the  cylinder  head  and 
also  from  each  other.  The  insulation  in  this  case  must  be 
something  capable  of  standing  quite  a  high  temperature. 

Two  lava  gas  tips,  having  a  small  round  hole  through  the 
tip  and  the  hole  enlarged  from  the  underside,  will  be  found 
to  answer  the  purpose  admirably.  The  wires  should  be 
threaded  on  the  outer  end  No.  2-56  and  four  brass  nuts  made 
and  tapped  the  same  size.  The  inner  ends  of  the  brass 
wires  are  drilled  to  correspond  with  the  size  of  the  platinum 
wire  used. 

A  piece  of  ^-inch  fiber  rod  is  drilled  the  size  of  the  brass 
wire,  after  which  the  outside  is  turned  down  to  fit  into  the 
enlarged  hole  of  the  lava  tip.  The  piece  is  then  cut  off, 
leaving  a  small  hub  of  the  original  diameter  of  the  rod  to 
project  on  the  outside  of  the  hole. 

The  platinum  wire  is  inserted  into  the  end  of  the  threaded 
brass  wire  and  the  fiber  bushing  placed  on.  Now  place  a 
small  quantity  of  sodium  silicate,  or  water  glass,  as  it  is  com- 
monly called,  into  the  hole  of  the  lava  tip  and  insert  the 


228 


GAS   ENGINE   CONSTRUCTION. 


parts  of  the  igniter.  Press  the  fiber  bushing  tightly  into  the 
enlarged  hole  of  the  gas  tip  and  set  in  a  warm,  dry  place 
until  the  sodium  silicate  is  thoroughly  hardened. 

Never  attempt  to  use  white  lead  or  other  mineral  cement 
for  this  purpose. 

When  the  two  igniters  have  been  prepared  and  cemented, 
the  holes  in  the  cylinder  head  can  be  drilled  and  reamed  to 
fit  the  bevel  of  the  tips. 

On  the  upper  portion  of  the  cylinder  head,  between  the 


2-56  THR.    PER  INCH 
RED  FIBRE 
LAVA  TIP 


FIG.  125. — IGNITER,  TWICE  FULL  SIZE. 

inlet  and  exhaust  valve,  lay  off  and  center-punch  two  points 
3^  inch  apart  for  the  igniters. 

Drill  with  a  J-inch  twist  drill,  holding  the  cylinder  head 
against  the  tail  stock  in  such  a  manner  that  the  holes  diverge 
toward  the  outside  of  the  cylinder  head  to  bring  the  points 
of  the  igniter  as  near  each  other  as  possible  on  the  inside  of 
the  cylinder  and  as  far  apart  as  possible  on  the  outside. 
This  is  to  prevent  the  spark  from  jumping  across  between 
the  outer  ends  of  the  igniter,  which  it  has  a  great  tendency 


IGNITER   AND    ELECTRICAL   CONNECTIONS.  229 

to  do  when  there  is  a  compression  in  the  cylinder,  as  that 
offers  a  great  resistance  to  the  spark. 

In  the  detail  drawing,  Fig.  125,  is  shown  the  proper 
positions  of  the  igniter  parts. 

Ream  the  holes  with  a  taper  reamer  from  the  inside  of  the 
cylinder  head  to  fit  the  taper  of  the  lava  tip. 

When  the  cylinder  head,  valve  and  valve  gearing  have  all 
been  finished  and  assembled,  the  igniters  can  be  put  in 
place. 

It  is  best  not  to  put  them  in  before  as  they  may  be  injured 
in  handling. 

A  little  sodium  silicate  is  first  put  into  the  holes  of  the 
cylinder  head  with  a  brush  and  the  igniters  firmly  pressed 
into  place  from  the  inside.  The  head  should  be  placed 
where  it  will  not  be  disturbed  for  several  hours  to  allow 
the  cement  to  harden  thoroughly. 

The  outer  ends  of  the  threaded  wire  of  the  igniters  should 
be  carefully  bent  away  from  each  other  to  prevent  the  spark 
from  jumping  across  where  the  brass  nuts  are  attached,  as 
that  point  would  otherwise  be  the  shortest  distance  between 
the  igniters.  When  the  igniters  are  in  place  in  the  cylinder 
head,  the  ends  of  the  platinum  wires  should  be  bent  toward 
each  other  until  they  almost  touch.  When  they  are  in  this 
position  the  spark  passing  between  the  points  will  be  of  a 
reddish  color  and  hot,  which  is  desirable  for  igniting  the 
charge  of  gas  and  air  in  the  cylinder. 

In  Fig.  126  is  shown  a  diagram  of  the  electrical  connec- 
tions required  for  this  engine. 

At  a  is  shown  the  battery  which  should  consist  of  two  or 
three  good  cells  capable  of  giving  a  high  electro-motive 
force,  and  having  considerable  capacity  for  endurance. 

The  spark  coil  is  shown  at  b.  The  wires  from  the  battery 
connect  to  the  binding  posts  on  the  base  of  the  coil  as  shown. 


230 


GAS   ENGINE   CONSTRUCTION. 


From  the  binding  posts  of  the  secondary  coil  the  wires 
pass  to  the  two  igniter  points  as  showrn. 

The  coil  should  be  placed  as  near  the  engine  as  possible 
to  keep  the  secondary  wires  from  grounding  or  sparking 
across  between  each  other.  On  one  of  the  primary  \vires, 
between  the  battery  and  the  coil,  is  introduced  the  contact 
c.  This  is  formed  of  two  pieces  of  spring  brass  fastened  at 
the  bottom  to  a  block  of  fiber.  The  ends  of  the  springs  are 
bent  at  a  right  angle  at  the  bottom  and  held  down  on  the 


FIG.  126. — ELECTRICAL  CONNECTIONS. 

block  of  fiber  by  machine  screws;  the  lower  ends  of  which 
are  also  used  to  clamp  the  ends  of  the  primary  wire. 

The  upper  ends  of  these  springs  are  bent  toward  each 
other  and,  at  the  points  where  they  touch  when  pressed 
together,  small  pieces  of  sheet  platinum  should  be  soldered. 

At  d  is  represented  the  hub  of  the  2-inch  gear  wheel  which 
operates  the  exhaust  valve  rod. 

The  contact  springs  are  held  in  position  behind  the  web 
ot  the  gear  wheel  and  close  to  the  hub.  The  hub  travels  in 
the  direction  shown  by  the  arrow.  These  points  should  be 


IGNITER   AND    ELECTRICAL   CONNECTIONS. 

"  t 


231 


in  contact  just  as  the  piston  reaches  the  end  of  the  in-stroke 
and  the  charge  of  gas  and  air  is  compressed  in  the  rear  of 
the  cylinder. 

When  the  moving  parts  are  in  this  position,  the  contact 
screw  of  the  interrupter  of  the  induction  coil  should  be 
adjusted  so  that  it  just  touches  the  spring.  This  is  neces- 
sary in  order  that  the  vibrator  shall  act  whenever  the  con- 
tact springs  on  the  engine  close  the  circuit. 


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*4-36  BRASS  SCREW 

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PLATINUM  CONTACTS 


FIG.  127. — IGNITER  CONTACTS  AND  FIBER  BLOCK. 

The  pin  shown  projecting  from  the  hub  of  the  gear  wheel 
is  made  from  a  piece  of  fiber  rod  -fw  inch  in  diameter. 

After  the  valve  gearing  has  been  finished,  and  the  gear 
wheels  marked  in  their  relative  positions,  rotate  the  fly- 
wheels of  the  engine  by  hand  and  locate  the  point  in  the 
cycle  at  which  the  explosion  of  the  charge  in  the  cylinder  is 
to  take  place.  This  can  be  found  by  referring  to  the  chapter 
treating  on  the  cycle  of  the  gas  engine. 

When  the  point  is  found  and  the  piston  placed  in  its  proper 
position  in  reference  to  the  explosion,  mark  the  hub  of  the 
gear  wheel  where  it  must  be  drilled  for  the  fiber  pin. 


232 


GAS   ENGINE   CONSTRUCTION. 


SECTIONAL  VIEW 


The  fiber  block  on  which  the  brass  contact  springs  are  set 
is  held  in  position  by  being  clamped  under  the  head  of  one 
of  the  cap  screws  of  the  bearing.  A  washer  should  be  placed 
under  the  head  of  the  screw. 

The  moment  of  contact  can  be  varied  slightly  by  tapping 
the  fiber  block  on  one  or  the  other  side  to  make  the  points 
touch  at  the  exact  instant. 

In  the  cut  of  the  complete  engine,  Fig.  130,  these  parts 
can  be  clearly  seen. 

Since  the  first  edition  of  this  work  was  published,  the 
particular  style  of  lava  tip  shown  in  this  chapter  has  been 
so  materially  changed  by  the  manufacturers  that  it  has  been 
found  very  difficult  to  make  the  igniters  "  spark  tight  "  under 

compression.  This  led  us  to  de- 
sign a  small  spark  plug  which 
could  be  easily  removed  for  exam- 
ination and  cleaning. 

The  igniter  pin  is  of  brass  sur- 
rounded by  a  lava  bushing  which 
extends  outside  the  cylinder  head 
far  enough  to  prevent  a  leakage  of 
the  spark.  The  igniter  pin  termin- 
ates in  a  platinum  point  inside  the 
cylinder.  The  second  platinum 

point  is  set  in  the  inner  end  of  the  screwed  brass  plug.     The 
construction  is  clearly  shown  in  Fig.  127  A. 

With  this  spark  plug  the  connections  shown  in  Fig.  126 
are  to  be  slightly  changed.  At  C  one  of  the  secondary 
wires  is  attached  to  the  projecting  end  of  the  igniter  pin, 
and  the  other  wire  is  to  be  clamped  under  the  head  of  one 
of  the  screws  of  the  cylinder  head  or  any  convenient  screw 
of  the  engine. 


FIG.   127  A. — IMPROVED 
IGNITER. 


Chapter  XXI. 
ASSEMBLING. 

CYLINDER     PARTS.       SHAFT,    CRANK    PIN    AND    FLY-WHEELS. 
INSERTING    CRANK    PIN.       PUTTING    CRANK    SHAFT    IN 
PLACE.       PISTON    AND    CONNECTING    ROD.       FIT- 
TING    FINISHED     PARTS    TO    BED     PLATE. 
DRILLING.    DRILLING  LUGS.    ASSEM- 
BLING ENGINE   FRAME. 


CHAPTER     XXI. 

ASSEMBLING. 

No  regular  routine  can  be  laid  down  for  the  builder  of 
this  engine  to  follow  in  assembling  the  different  parts. 
Some  of  the  parts  cannot  be  assembled  until  certain  other 
parts  have  been  completed. 

For  instance,  the  cylinder  parts  cannot  be  permanently 
and  correctly  put  together  until  the  side  rods  and  bearings 
have  been  completed  and  fitted. 

In  assembling  the  cylinder  parts,  put  the  side  rods  into 
the  main  bearings,  which  are  held  in  line  by  inserting  a 
piece  of  shaft  through  both  of  them.  Fasten  the  rods  into 
the  bearings  by  driving  in  the  steel  keys. 

Place  the  forward  cylinder  collar  in  its  proper  position  on 
the  side  rods  and  insert  into  it,  from  the  back,  the  front  end 
of  the  cylinder  tube. 

Slide  the  cylinder  supports  on  the  side  rods.  Place  the 
end  of  the  brass  jacket  tube  into  its  position  in  the  front 
cylinder  collar,  after  which  the  back  cylinder  collar  is  placed 
on  the  side  rods  and  cylinder  tube.  The  two  nuts  can  now 
be  screwed  on  the  side  rods  by  which  the  cylinder  parts  are 
securely  clamped  together.  This  should  be  done  with  the 
bearings  and  supports  setting  on  a  level  surface. 

Should  it  become  necessary  to  remove  the  cylinder  from 
the  rods,  its  parts  will  be  held  firmly  together  if  the  boring 
of  the  cylinder  collars  and  turning  down  of  the  tubing  was 
accurately  done. 


236  GAS   ENGINE   CONSTRUCTION. 

When  the  shaft,  crank  pin,  and  fly-wheels  are  ready  to  be 
put  together,  the  two  pieces  of  shaft  must  be  driven  into 
their  respective  fly-wheels. 

A  wood  mallet  is  best  to  use  for  this  purpose,  and  the 
blows  should  be  struck  squarely  on  the  end  to  prevent 
springing  the  shaft. 

After  the  two  parts  have  been  drilled  for  steel  pins,  as 
shown  in  Fig.  95,  and  securely  pinned,  they  should  be 
attached  by  forcing  the  crank  pin  into  place  in  both  wheels, 
keeping  the  two  pieces  of  shaft  in  line  with  each  other.  A 
large  vise  is  the  best  thing  to  use  for  this  purpose,  but  it 
must  be  large  enough  in  the  throat  so  that  the  jaws  shall 
come  to  the  crank  pin  boss. 

If  it  is  found  necessary  to  drive  the  parts  together,  one  fly- 
wheel can  have  the  pin  driven  into  it  with  a  mallet,  and  then 
placing  this  wheel,  with  the  crank  pin  boss  supported  from 
the  under  side,  on  a  good,  solid  foundation,  place  the  other 
wheel  above  with  the  shafts  in  line  and  strike  with  the 
mallet  on  the  crank  pin  boss.  Use  caution  when  driving 
these  parts  together,  and  do  not  spring  the  crank  pin  by 
pressing  the  outer  rims  together  before  the  crank  pin  is 
home  in  both  wheels.  Before  screwing  the  two  cap  screws 
into  the  ends  of  the  crank  pin,  test  the  complete  shaft  for 
alignment.  If  the  two  fly-wheels  are  exactly  the  same  diam- 
eter and  straight  across  the  face,  a  steel  rule  or  straight 
edge  placed  across  the  two  wheels  will  show  if  the  shaft  is 
in  line.  If  found  out  of  line,  take  hold  of  the  two  rims  of  the 
fly-wheels  opposite  the  crank  pin  and  twist  one  of  the  wheels 
on  the  pin  until  the  complete  shaft  lines  up.  Then  insert 
the  screws  in  the  ends  of  the  pin  and  clamp  the  washers 
down  tight  on  the  crank  pin  boss. 

The  completed  crank  shaft  is  then  ready  to  mount  in  the 
bearings. 


ASSEMBLING.  f  237 

When  the  bed  plate  is  ready  for  the  engine  proper,  the 
cylinder  side  rods  and  bearings  are  fastened  together,  with 
the  cylinder  supports  in  place,  and  a  piece  of  solid  shaft 
passed  through  the  bearings. 

Place  these  parts  on  the  bed  plate  in  their  proper  posi- 
tion, as  shown  in  Fig.  128. 

With  a  scriber  mark  on  the  bed  plate  the  position  of  the 
front  holes  in  the  main  bearing  through  the  holes  alreadv 


\ 

.^•ta^^J 

lp} 


FIG.  128. — CYLINDER,  SIDE  RODS  AND  BEARINGS  ASSEMBLED 
AND  BOLTED  TO  BED  PLATE. 

drilled  in  their  bases  ;  also  mark  position  of  one  hole  of  each 
cylinder  support. 

Lift  the  engine  parts  from  the  bed  plate  and  center-punch 
the  places  marked. 

Also  center-punch  the  four  lugs  on  the  bottom  of  the  bed 
plate.  Drill  the  latter  holes  first  with  a  ^-inch  drill.  Use 
these  holes  to  fasten  the  bed  plate  on  a  piece  of  hardwood 
board,  which  will  cover  the  entire  bottom  of  the  bed  plate. 

This  piece  of  board  is  for  the  back  center  of  the  lathe  to 


238  GAS   ENGINE   CONSTRUCTION. 

rest  against. when  drilling  the  holes  in  the  top  of  the  bed 
plate. 

Drill  the  four  screw  holes  marked  with  a  No.  4  twist  drill 
and  tap  them  ^-inch  20. 

Replace  the  engine  parts  and  fasten  them  down  with 
J-inch  cap  screws,  then  the  remaining  holes  can  be  marked. 
Remove  the  engine  parts  again  and  drill  and  tap  the  remain- 
ing holes,  after  which  the  piece  of  board  can  be  removed 
from  the  bottom  of  the  bed  plate  and  the  engine  parts 
replaced  and  fastened  down,  as  shown  in  Fig.  128. 

In  placing  the  frame  of  the  engine  in  position  on  the  bed 
plate,  the  most  important  thing  to  consider  is  the  proper 
location  of  the  main  bearings  in  reference  to  the  depression 
of  the  bed  plate  where  the  fly-wheels  are  to  be  placed. 

If  this  is  neglected  it  may  be  found  on  mounting  the  fly- 
wheels and  shaft  in  the  bearings  that  the  wheels  will  rub  on 
the  bed  plate. 

In  the  size  engine  here  described  the  centers  of  the  bear- 
ings should  be  just  5  inches  apart,  as  shown  in  detail 
drawings. 

When  the  cylinder,  supports,  side  rods,  and  main  bearings 
are  assembled  and  screwed  to  the  bed  plate,  as  in  Fig.  128, 
the  crank  shaft  and  fly-wheels  can  be  mounted  into  position. 
To  do  this  unscrew  the  supports  from  the  bed  plate  and 
remove  the  two  nuts  from  the  ends  of  the  side  rods.  The 
cylinder  and  supports  can  then  be  slid  from  the  rods.  Next 
unscrew  the  main  bearings  from  the  bed  plate  and  slide 
them  on  the  shaft  on  their  respective  sides. 

Replace  the  bearings  on  the  bed  plate  with  the  fly-wheels 
between  them  and  screw  into  place  again.  The  cylinder 
and  bearings  can  then  be  slid  on  the  side  rods  and  screwed 
to  the  bed  plate. 

In  assembling  the  piston  and  connecting  rod  parts,  the 


ASSEMBLING. 


239 


rod  and  piston  pin  are  finished  and  placed  in  position  in  the 
piston  casting  before  the  shell  of  the  piston  is  placed  on  the 
casting-.  In  Fig.  128  the  casting  and  shell  are  shown  stand- 
ing beside  the  bed  plate  of  the  partially  finished  engine.  In 
Fig.  72  the  casting  is  shown  with  the  pin  inserted.  It  will 
be  seen  that  the  ends  of  the  pin  are  rounded  to  conform  to 
the  curve  of  the  inside  of  the  piston  shell. 


FIG.  129. — MAIN  PARTS  OF  ENGINE  ASSEMBLED. 

The  connecting  rod  is  lined  up  and  both  ends  pinned  to 
the  steel  rod,  after  which  the  rod  must  be  inserted  between 
the  lugs  of  the  piston  casting  and  the  piston  pin  put  through 
the  two  and  pinned  into  place. 

The  shell  is  then  slid  on  the  casting  and  fastened  there  by 
the  two  screws.  The  piston  is  then  ready  for  the  fitting  of 


240  GAS   ENGINE   CONSTRUCTION. 

the  packing  ring  on  the  back  of  the  casting.  After  this  is 
fitted  a  piece  of  asbestos  wicking  can  be  wrapped  around 
the  groove  of  the  packing  ring  and  oiled,  and  a  little  graph- 
ite should  be  sprinkled  on  the  oiled  wicking.  Slide  the 
piston  into  the  cylinder  with  the  screws  of  the  packing  ring 
loose.  After  the  piston  and  ring  are  inside  the  cylinder, 
tighten  up  the  screws,  which  will  set  the  packing  against 
the  cylinder  shell. 

The  connecting  rod  can  now  be  attached  to  the  crank  pin. 
The  work  will  then  have  the  appearance  shown  in  Fig.  129. 

The  cylinder  head  should  be  finished  next  by  boring  it 
for  the  valves  and  igniter.  After  these  parts  are  completed 
and  the  valves  in  place,  the  valve  gearing  should  be 
assembled. 

In  placing  the  exhaust  valve  in  position  the  end  of  the 
lever  should  come  on  a  line  with  the  center  of  the  side  rods, 
then,  when  the  valve  rod  bearings  are  screwed  on  to  the 
ends  of  the  lugs  of  the  cylinder  collars,  the  valve  rod  will 
also  line  up  with  the  side  rods  and  have  a  very  neat  appear- 
ance. 

It  may  be  necessary  to  give  the  lever  of  the  exhaust  valve 
a  slight  offset  to  meet  the  end  of  the  valve  rod.  This  will 
depend  upon  how  accurately  the  exhaust  valve  has  been 
put  in  position. 

The  governor  should  be  completed  and  put  in  position 
next. 

Be  sure  that  the  catch  pins  come  in  line.  The  pin  pro- 
jecting from  the  lower  side  of  the  governor  lever  is  made 
square  to  allow  for  any  slight  variation  in  the  lining  up  of 
the  pins. 

In  fitting  the  governor  to  the  valve  rod  bearing  the  parts 
should  not  bind,  as  the  governor  lever  must  move  up  and 
down  easily. 


ASSEMBLING. 


24I 


There  should  not  be  any  lost  motion,  however,  which 
would  allow  the  governor  lever  to  move  from  side  to  side, 
as  a  slight  movement  in  this  direction  at  the  point  where 
the  lever  attaches  to  the  valve  rod  bearing  would  be  multi- 
plied to  such  an  extent  at  the  catch  pins  that  they  might 
miss  each  other.  After  the  exhaust  valve,  valve  rod  and 


FIG.  130. — THE  FINISHED  ENGINE. 

governor  are  in  place  the  indentation  in  the  top  of  the  valve 
rod  can  be  marked  and  afterwards  filed. 

In  filing  this  indentation  great  care  must  be  exercised 
to  get  it  in  exactly  the  right  place  and  at  the  proper 
depth. 

The  starting  handle  should  be  fitted  and  the  engine  tried 
with  it  to  see  how  the  governor  will  work. 
•     The  governor  weight  can  be  moved  to  different  positions 


242  GAS   ENGINE   CONSTRUCTION. 

on  the  lever,  and  the  adjusting  thumb  screw  used  to  var^r 
the  tension  of  the  spring. 

By  running  the  engine  with  the  starting  handle  it  can  be 
brought  up  to  speed  enough  to  test  the  working  of  the  gov- 
ernor. 

The  igniter  should  be  put  in  place  last,  after  all  the  other 
parts  are  finished  and  in  position,  as  the  pieces  composing 
this  are  so  much  more  delicate  than  the  others  and  are 
liable  to  be  broken. 

Directions  for  finishing  up  these  parts  will  be  found  in 
Chapter  XX. 

The  completed  engine  is  shown  in  Fig.  130. 


Chapter  XXII. 
REGULATING  AND   STARTING. 

STARTING     HANDLE.       TESTING     INLET     VALVE.       ADJUSTING 

EXHAUST  VALVE.      TESTING  CONTACT  SPRINGS.      ADJUST- 

ING  AND  TESTING  IGNITER.      ADJUSTING  GOVERNOR. 

STARTING     THE      ENGINE.        REGULATING     THE 

AMOUNT     OF     GAS.        PROPORTIONING     THE 

CHARGE.      GAS   SUPPLIES  FOR  ISOLATED 

ENGINES.       VAPORIZERS    AND 

CARBURETERS. 


CHAPTER  XXII. 

REGULATING  AND    STARTING. 

After  the  machine  work  has  been  completed  on  the  engine 
proper  a  starting  handle  must  be  made,  the  dimensions  of 
which  are  given  in  the  detail  drawings,  Fig.  131.  This  is 
made  of  a  casting  of  iron  and  the  handle  is  of  wood,  turning 
on  a  piece  of  J-inch  steel  rod.  A  washer  and  screw  prevent 
the  wood  handle  from  sliding  off  the  rod. 

At  the  opposite  end  of  the  crank  a  two-jaw  clutch  is  cast, 
and  through  this  part  of  the  casting  a  -J  inch  hole  is  to  be 
drilled  to  enable  the  handle  to  be  placed  on  the  end  of  the 
crank  shaft  which  has  been  turned  down.  The  pin  driven 
into  this  piece  of  the  shaft,  as  described  and  shown  in  Chap- 
ter XIV.,  is  to  engage  with  the  clutch  of  this  handle,  and  by 
this  means  the  engine  can  be  turned  easily  by  hand. 

An  examination  of  the  shape  of  the  clutch  will  show  that 
so  long  as  pressure  is  exerted  by  the  hand  turning  the  crank 
the  clutch  will  engage  with  the  pin  on  the  shaft.  As  soon 
as  the  engine  starts  off  of  itself,  however,  the  shaft  and  pin 
will  travel  faster  than  the  handle  and  passing  along  the 
incline  of  the  clutch  will  throw  it  out  of  gear.  The  handle 
is  then  slid  off  the  end  of  the  shaft.  The  fit  of  the  handle  on 
the  shaft  must  be  an  easy  one,  that  it  may  be  removed  with- 
out difficulty  after  the  engine  has  started. 

By  the  use  of  the  starting  handle  the  various  parts  of  the 
engine  can  be  tested  ;  such  as  the  inlet  and  exhaust  valves, 
electrical  connections  and  igniter,  governor,  etc. 


246 


GAS   ENGINE   CONSTRUCTION. 


When  the  piston  is  traveling  forward  on  the  admission 
stroke  of  the  cycle  the  inlet  valve  should  open  and  air  will 
be  drawn  into  the  cylinder.  This  being  a  description  of  the 
testing  of  the  valves  the  gas  is  not  as  yet  turned  on. 

The  spring  of  the  inlet  valve  must  be  adjusted  to  let  the 
valve  open  easily  on  this  part  of  the  stroke,  but  yet  must  be 
sufficiently  strong  to  hold  the  valve  closed  if  the  piston  is 


FIG.  131. — CRANK  HANDLE. 

traveling  in  this  same  forward  direction  and  the  exhaust 
valve  is  held  open  by  the  governor.  This  can  be  determined 
by  turning  the  engine  and  holding  the  exhaust  valve  open, 
either  by  depressing  the  governor  lever  or  holding  back  on 
the  exhaust  valve  lever.  The  valves  can  be  tested  for  leaks 
by  turning  the  engine  by  the  handle  and  stopping  at  the 
end  of  the  compression  stroke  of  the  cycle. 


REGULATING  AND   STARTING.  247 


The  engine  should  be  turned  to  see  that  the  exhaust  valve 
opens  at  the  proper  moment.  It  should  begin  to  open  just 
before  the  piston  reaches  the  forward  end  of  the  cylinder  on 
the  expansion  stroke  of  the  cycle,  and  the  valve  should  close 
just  as  the  piston  reaches  the  back  end  of  the  cylinder  on 
the  exhaust  stroke. 

If  is  found  that  the  valve  is  not  set  exactly  right  it  can  be 
varied  by  sliding  the  2-inch  gear  wheel  from  the  gear  stud 
and  revolving  it  forward  or  back  one  tooth  at  a  time  until 
the  proper  position  is  reached.  A  variation  can  also  be 
made  by  the  adjusting  screw  on  the  end  of  the  exhaust  valve 
lever. 

The  electrical  connections  should  also  be  tested  to  see 
that  the  contact  occurs  at  just  the  right  time.  The  spring 
contacts  should  touch  each  other  just  the  instant  the  piston 
is  coming  to  rest  at  the  end  of  the  compression  stroke.  The 
two  platinum  points  of  the  igniter  should  be  separated  by 
only  about  -fa  inch.  To  see  the  spark  the  cylinder  head  can 
be  removed  and  held  in  position  on  the  foundation  with  the 
inside  of  the  head  in  view.  When  the  engine  is  then  rotated, 
if  the  connections  are  all  right  according  to  the  diagram  in 
Chapter  XX,  the  spark  can  be  seen  at  every  second  revolu- 
tion of  the  engine. 

The  two  small  pipes  of  the  water  jacket  must  be  connected 
up  with  the  water  supply. 

Where  the  engine  is  to  be  used  near  a  water  connection  a 
piece  of  rubber  hose  can  be  used  between  the  water  faucet 
and  the  lower  pipe  of  the  jacket,  and  a  waste  pipe  connected 
with  the  pipe  in  the  top  of  the  jacket  and  the  waste  water 
allowed  to  runaway.  The  water  should  not  be  supplied  too 
freely,  as  it  is  much  better  to  allow  the  engine  cylinder  to 
remain  quite  warm  than  to  keep  it  too  cool  by  a  large  sup- 
ply of  water.  Where  running  water  is  not  convenient,  a 


248  GAS   ENGINE   CONSTRUCTION. 

circulating  tank  must  be  used.  This  can  be  made  from  a 
small  sized  galvanized  ash  can  or  any  other  suitable  reser- 
voir. If  the  lower  pipe  of  the  water  jacket  is  connected 
with  the  tank  by  a  pipe  entering  near  the  bottom  of  the 
tank  and  the  outlet  of  the  jacket  is  connected  by  a  pipe 
entering  the  tank  near  the  top,  a  circulation  of  the  water 
will  be  kept  up  and  the  cvlinder  will  remain  cool  enough. 

The  reservoir  should  hold  twelve  or  fifteen  gallons  for 
an  engine  of  this  size. 

The  water  level  in  the  tank  must  be  higher  than  the  point 
of  entrance  of  the  pipe  from  the  top  of  the  water  jacket. 

Should  it  be  allowed  to  get  below  that  level  there  wilL 
be  no  circulation  and  the  cylinder  will  become  overheated. 

The  tank  should  be  placed  near  the  engine  and  the  pipes 
should  have  as  few  bends  as  possible.  Use  nothing  smaller 
than  -J-inch  iron  pipe  for  this  purpose. 

If  all  these  different  parts  are  found  to  be  in  proper  order 
the  gas  may  be  turned  on  and  the  engine  given  one  or  more 
complete  revolutions  with  the  starting  handle  to  get  it  into 
operation.  It  is  well  to  set  the  governor  for  a  low  speed  at 
the  first  trial  to  be  sure  that  all  parts  of  the  engine  are  firmly 
fastened  together.  To  set  the  governor,  loosen  up  the  speed 
regulating  screw  and  turn  the  engine  by  hand  until  the  gov- 
ernor works  by  catching  the  pin  of  the  exhaust  valve  lever 
and  holding  the  exhaust  valve  open. 

After  the  engine  has  been  started  and  allowed  to  run  light 
at  a  low  speed,  to  see  that  all  its  parts  are  in  working  order, 
the  speed  can  be  increased  by  screwing  down  the  speed 
regulating  screw  on  the  governor  lever. 

It  will  be  necessary  to  place  a  stop  cock  on  the  gas  inlet 
pipe  to  regulate  the  amount  of  gas  admitted  to  the  engine. 
This  stop  cock  should  be  placed  on  the  gas  ring  of  the  inlet 
valve,  as  shown  in  the  cut  of  the  finished  engine. 


REGULATING  AND   STARTING.  249 


• 


A  little  experimenting  will  be  necessary  to  determine  the 
best  proportions  of  the  charge  of  explosive  mixture  to  admit 
to  the  cylinder.  When  the  stop  cock  is  once  set  where  the 
best  result  is  obtained  under  the  prevailing  conditions,  the 
screw  in  the  end  of  the  plug  of  the  stop  cock  should  be 
tightened  down  to  hold  the  stop  cock  in  that  position,  and 
the  turning  on  and  off  of  the  gas  supply,  at  stopping  and 
starting,  should  be  done  with  a  separate  stop  cock  at  any 
oAer  convenient  point  on  the  supply  pipe. 

The  exact  proportions  of  the  charge  of  gas  and  air  will 
vary  under  different  conditions.  The  gas  in  some  towns 
will  be  found  richer  than  in  others.  The  richer  the  gas  the 
smaller  the  quantity  required  in  each  charge  and  the  poorer 
the  quality  of  the  gas  the  more  of  it  will  be  required  to 
obtain  the  same  result  in  the  engine. 

It  has  been  found  that  the  best  results  are  obtained  with 
an  average  proportion  of  i  part  of  gas  to  12  parts  of  air. 

This  is  based  on  the  supposition  that  the  gas  is  of  Ai 
quality  city  coal  gas.  With  an  inferior  quality  it  may  be 
found  necessary  to  increase  the  quantity  of  gas  in  the  mix- 
ture to  a  proportion  of  I  part  of  gas  to  8  parts  of  air. 

In  practice  the  best  results  will  be  obtained  with  mixtures 
proportioned  between  these  two  extremes. 

Where  gas  is  not  obtainable,  the  engine  must  be  supplied 
with  a  carbureter,  or  vaporizer,  to  generate  gas  from  gaso- 
line, etc.  In  the  following  chapter  will  be  found  a  design 
for  a  carbureter. 

A  vaporizer  is  not  recommended  by  the  writers  for  so 
small  an  engine.  They  are  complicated  and  consequently 
get  out  of  order  easily.  In  the  case  of  automobiles  they  are 
necessary,  as  they  are  much  lighter  than  a  carbureter,  besides 
taking  up  so  much  less  room.  We  should  not  advise  an 
amateur  to  attempt  the  construction  of  a  vaporizer. 


Chapter  XXIII. 
ON   CARBURETERS. 

DESIGN   FOR  CHEAP   CARBURETER.      DESCRIPTION   OF  CARBU- 
RETER   PARTS.       SAFETY   DEVICE.       FITTING  THE    INSIDE 
OF       CARBURETER.        SPRING       HOOPS.        CAPILLARY 
PARTITIONS.         CHARGING     THE       CARBURETER. 
CONNECTING     WITH     THE     ENGINE.       PRAC- 
TICAL WORKING  OF  THE   CARBURETER. 
AMOUNT   OF    GASOLINE    TO    USE. 
ADVANTAGES     OF     THIS 
CARBU  RETER. 
CAUTIONS. 


CHAPTER     XXIII. 

CARBURETERS. 

Where  coal  or  natural  gas  is  not  obtainable,  it  will  be 
found  n.cessary  to  furnish  a  substitute  for  supplying  the 
engine  with  an  explosive  mixture. 

Gasoline  will  be  found  to  answer  this  purpose  admirably, 
but  some  apparatus  is  necessary  to  convert  the  gasoline  into 
a  gas  before  it  can  be  used  for  combustion  in  the  gas  engine 
cylinder. 

A  carbureter  will  be  found  to  be  the  best  adapted  for  this 
purpose,  as  the  gasoline  will  be  entirely  enclosed  and  free 
from  danger. 

The  carbureter  shown  in  Fig.  132  is  one  designed  by  the 
authors  several  years  ago,  and  has  been  found  to  do  excel- 
lent work.  There  is  nothing  about  it  either  to  wear  out  or 
get  out  of  order. 

The  body  of  the  carbureter  A  may  be  a  piece  of  brass  tub- 
ing about  6  inches  in  diameter  and  1 8  inches  long.  It  can 
also  be  made  up  of  heavy  sheet  tin  or  copper  with  a  lock 
joint,  the  same  as  a  stovepipe  is  put  together.  Another  way 
is  to  use  a  piece  of  6-inch  iron  pipe  threaded  at  each  end,  on 
which  two  6-inch  caps  can  be  screwed  to  close  up  the  ends. 
This  is  a  matter  which  the  builder  can  decide  for  himself,  as 
it  will  depend  on  his  facilities  which  mode  of  construction 
he  chooses.  In  the  cut  is  shown  a  cap  B  on  one  end  of  the 
tube  and  a  flange  is  attached  to  the  opposite  end,  to  which 
the  head  C  is  fastened  by  screws. 


254 


GAS   ENGINE   CONSTRUCTION. 


At  D  is  a  J-inch  stopcock.  This  is  screwed  into  one  end 
of  a  -J-inch  elbow,  which  is  screwed  to  a  ^-inch  close  nipple 
tapped  into  the  head  B. 

This  stopcock  is  the  inlet  for  the  air  which  is  to  be  car- 
bureted and  is  connected  to  the  elbow  and  placed  in  an 
upright  position  that  gasoline  may  be  poured  into  it  when  it 
is  necessary  to  charge  the  carbureter. 

In  the  opposite  head  is  placed  the  stopcock  E,  which  con- 


RUBBERTUBE 
TO  INLET  VALVE 


-  STEEL  SPRING 


FIG,  132. — CARBURETER. 

trols  the  outlet  of  the  carbureted  air  or  gas  which  passes 
through  the  rubber  hose  on  its  way  to  the  inlet  valve  of  the 
gas  engine. 

F  represents  a  small  safety  device  to  prevent  any  possi- 
bility of  the  flame  from  the  gas  engine  cylinder  reaching  the 
carbureter.  This  can  be  placed  next  the  stopcock  E,  as 
shown  in  the  cut,  or  in  the  tubing  nearer  the  inlet  valve. 

A  cross  section  of  this  device  is  shown  in  the  lower  part 
of  the  cut.  F  represents  one  of  the  two  saucer  shaped 


CARBURETERS.  255 

pieces  of  copper  or  other  ductile  metal.  These  are  made  of 
two  sheet  metal  disks  2  inches  in  diameter  and  about  ^¥  inch 
thick.  They  are  formed  to  shape  by  hammering  with  a  ball 
pein  hammer  into  a  depression  cut  or  hammered  in  a  piece 
of  hard  wood.  The  edges  should  be  left  flat,  as  shown.  In 
the  center  of  these  pieces  a  hole  is  punched  and  a  piece  of 
brass  tubing  driven  through  and  soldered.  /  represents  a 
piece  of  fine  brass  wire  gauze  which  is  cut  into  a  disk  the 
same  diameter  as  the  pieces  F,  and  when  placed  in  the  posi- 
tion it  is  to  occupy  between  the  two  saucer-shaped  pieces  F 
the  edges  of  all  three  are  soldered  together.  The  material 
for  this  device  can  be  procured  in  any  tin  shop. 

We  now  come  to  the  most  important  part — the  fitting  of 
the  inside  of  carbureter. 

Gasoline  is  a  liquid  which  possesses  the  property  of  rapid 
evaporation  when  placed  in  intimate  contact  with  air,  and 
the  more  thoroughly  the  two  can  be  brought  into  relation 
with  each  other  the  richer  will  be  the  gas  produced.  In 
this  carbureter  the  desired  result  is  obtained  by  passing  the 
incoming  air  through  a  great  number  of  thicknesses  of  bur- 
lap or  other  coarse  cloth. 

In  the  lower  half  of  Fig.  132  G  represents  a  piece  of  thin 
spring  brass  or  spring  steel  about  20  inches  in  length  for  this 
diameter  of  carbureter  and  f  inch  wide.  It  is  bent  around 
with  the  fingers  until  it  forms  a  hoop  about  5  inches  in 
diameter,  and  while  held  in  this  position  is  laid  down  on  a 
piece  of  burlap  H  about  9  inches  square.  Holding  the  spring 
together  with  the  fingers  of  one  hand,  the  corners  of  the 
burlap  are  folded  over  into  the  center  of  the  spring,  after 
which  they  are  gathered  into  one  hand  and  the  spring 
thereby  prevented  from  distending. 

The  carbureter  should  be  previously  set  on  one  end  with 
the  upper  end  open.  The  spring  and  burlap  are  placed 


256  GAS   ENGINE   CONSTRUCTION.    . 

down  into  the  end  of  the  carbureter,  and  the  spring  is  then 
allowed  to  expand  slowly  by  letting  the  corners  of  the  bur- 
lap slide  through  the  fingers.  The  corners  are  carefully 
folded  over  into  the  center  of  the  hoop  and  another  hoop 
and  piece  of  burlap  prepared  and  placed  in  position  above 
the  first  one.  This  is  continued  until  the  carbureter  is  filled. 
Each  hoop  should  be  pushed  firmly  against  the  one  preced- 
ing it  in  order  to  get  in  as  many  as  possible.  The  spring 
hoops  are  for  the  purpose  of  holding  the  burlap  pieces 
snugly  against  the  tube  and  preventing  air  from  passing 
through  the  carbureter  unless  it  shall  pass  through  the  bur- 
lap partitions. 

In  a  carbureter  18  inches  in  length  about  forty  or  more  of 
these  hoops  can  be  placed. 

When  the  carbureter  is  placed  in  its  normal  position,  as 
shown  in  the  cut,  the  burlap-covered  hoops  will  be  standing 
on  edge.  If  gasoline  is  now  introduced  through  the  stop- 
cock by  placing  a  funnel  therein,  it  will  flow  along  the  bot- 
tom of  the  carbureter,  and  the  burlap  on  each  hoop  will  at 
once  exert  its  capillary  attraction  and  become  saturated 
with  gasoline. 

If  the  rubber  tube  from  the  outlet  E  be  now  connected 
with  the  gas  ring  of  the  inlet  valve  of  the  engine,  the  for- 
ward motion  of  the  piston  in  the  cylinder  will  act  as  a  pump, 
and  a  portion  of  the  air  drawn  into  the  inlet  valve  will  pass 
through  the  carbureter. 

As  each  particle  of  air  passing  through  the  carbureter 
must  of  necessity  pass  through  each  of  the  burlap  partitions, 
it  is,  therefore,  brought  in  intimate  contact  with  the  gaso- 
line with  which  the  burlap  is  saturated.  These  particles  of 
gasoline  are  absorbed  by  the  air  in  its  passage  through  the 
carbureter,  and  the  combination  forms  a  combustible  gas. 

A  charge  of  one  gallon  of  gasoline  is  all  that  should  be 


CARBURETERS.  257 

placed  in  the  carbureter  at  one  time.  This  will  fill  it  about 
half  full,  and  the  partitions  of  burlap  will  remain  saturated 
as  long  as  any  gasoline  is  collected  in  the  bottom  of  the 
carbureter. 

If  desired,  a  small  plug  could  be  screwed  into  one  head  of 
the  carbureter  about  an  inch  from  the  bottom. 

This  could  be  carefully  removed  if  it  were  suspected  that 
the  charge  of  gasoline  was  exhausted. 

If  no  gasoline  shows  when  the  plug  is  loosened,  the  car- 
bureter needs  recharging. 

A  small  stopcock  would  be  a  quicker  test,  but  we  should 
not  advise  using  one  because  of  the  danger  of  accidental  loss 
of  gasoline. 

The  stopcocks  D  and  E  should  be  closed  as  soon  as  the 
engine  is  stopped  and  opened  again  before  starting.  The 
stopcock  of  the  inlet  valve  should  only  be  used  to  graduate 
the  flow  of  gas,  and  when  the  proper  opening  has  been 
found  by  experiment,  the  stopcock  should  be  tightened  up 
and  remain  in  that  position. 

This  carbureter  possesses  several  advantages,  as  it  is 
cheap,  yet  effective.  There  can  be  no  waste  of  gasoline  if 
the  stopcocks  and  connections  are  tight. 

The  carbureter  can  be  left  charged  for  weeks  and  is  as 
ready  to  supply  gas  at  the  end  of  that  time  as  it  would  be  if 
only  freshly  charged. 

If  made  up  of  sheet  metal,  the  heads  may  be  soldered  in. 
One  head  can  be  put  in  before  the  hoops  are  placed  in  posi- 
tion, and  the  other  head  after  these  are  in  place.  In  this 
case  all  joints  must  be  securely  soldered. 

If  the  carbureter  is  made  from  a  piece  of  pipe  and  the 
heads  screwed  on,  white  lead  should  be  used  in  the  threads 
to  insure  their  being  perfectly  tight. 

To  the  experimenter  who  is  unaccustomed  to  the  hand- 


GAS  ENGINE  CONSTRUCTION. 

ling  of  gasoline  a  few  words  of  advice  and  caution  are 
desirable. 

Gasoline  at  ordinary  temperatures  gives  off  a  heavy  and 
inflammable  gas,  so  that  if  a  bottle  or  can  of  this  oil  be  left 
open  one  may  see,  by  reason  of  its  greater  density,  a  thin 
stream  of  the  vapor  issuing  from  the  opening  and  pouring 
down  the  sides  on  to  the  table  and  then  to  the  floor.  Should 
a  burning  match  be  in  its  path  the  gas  will  at  once  catch  fire 
and  the  flame  will  run  along  up  the  stream  to  the  can. 

So  every  precaution  must  be  taken  when  handling  gaso- 
line that  no  one  is  near  by  who  is  smoking,  nor  must  any 
flame  be  burning.  The  room  windows  should  be  open,  so 
that  the  ventilation  will  prevent  the  gas  from  accumulating 
on  the  room  floor. 

Should  any  of  the  liquid  catch  fire  the  flames  may  be 
smothered  by  throwing  on  them  sand,  earth,  or  flour.  A 
fire  in  a  closed  room  can  be  extinguished  by  the  use  of  liquid 
ammonia. 

Always  keep  your  gasoline  can  tightly  closed  and  in  a. 
cool,  safe  place. 


Chapter  XXIV. 
ENGINE    DETAILS    AND    THEIR   DESIGN. 

CLASSIFICATION   OF   PARTS.      BED    PLATE.      CYLINDER   DIMEN- 
SIONS.     SPEED.      LENGTH    OF   STROKE.      WEIGHT  OF  FLY- 
WHEELS.     COUNTER-WEIGHTS.      MAIN  SHAFT.      BEAR- 
INGS.     OILERS.      CRANK  PIN.      CONNECTING  ROD. 
PISTON       PIN.         PISTON.         CYLINDER      AND 
HEAD.       INLET     AND     EXHAUST     PORTS 
AND    VALVES.       SIDE     RODS.       GOV- 
ERNORS.      IGNITERS. 
MUFFLERS. 


CHAPTER    XXIV. 

ENGINE   DETAILS   AND   THEIR   DESIGN. 

Forms  and  styles  of  engines  for  many  different  purposes 
vary  so  much  that  it  is  possible  in  this  chapter  only  to  give 
sundry  hints  and  suggestions  and  to  indicate,  in  a  general 
way,  some  of  the  principles  of  design  which  apply  especially 
to  gas  engine  work.  So  that,  while  our  object  is  to  encourage 
the  amateur  and  small  motor  builder  all  we  can,  we  do  not 
advise  our  readers  to  attempt  the  design  and  construction 
of  engines  of,  say,  three  horse  power  or  more  without  being 
farther  informed  in  the  subjects  of  machine  design,  strength 
of  materials,  etc. 

In  order  to  readily  classify  the  various  parts  of  an  engine 
we  can  divide  them  into  fixed  and  moving,  and  again,  accord- 
ing to  size  and  importance,  into  primary  and  secondary  ; 


(  Bed  plate. 
/  Primary       >  Cylinder 

Fixed  Parts  /  Cylinder  head- 

)  I    Bearings. 

(  0  )  Igniter. 

\  Secondary  / 

Water  jacket. 

Piping. 
Muffler. 


262 


GAS   ENGINE   CONSTRUCTION. 


Moving  parts 


Primary 


Secondary 


Piston. 

Connecting  rod. 

Crank  shaft. 

Fly-wheels. 

Valve  shaft. 

Valves. 

Valve  levers. 

Governor. 

Cams. 

I  Igniter  lever. 
\  Pulley. 


The  bed  plate  or  supporting  frame  is  a  part  which  will 
vary  so  much,  according  to  the  use  for  which  an  engine  is 
designed,  that  we  will  but  point  out  what  its  general  func- 
tions must  be,  and  they  are  principally  two  in  number :  first, 
to  resist  the  explosion  which  tends  to  separate  the  cylinder 
from  the  crank  shaft ;  second,  to  keep  the  whole  machine 
firmly  fixed  in  place  so  as  to  resist  the  pull  of  the  belt  by 
which  the  power  is  transmitted,  or  the  turning  effort  which 
will  ensue  when  coupled  to  a  shaft  or  dynamo. 

In  the  model  engine  which  is  the  subject  of  this  book  the 
first  of  the  above  requirements  is  filled  by  the  two  side  rods, 
making  direct  connection  from  the  cylinder  to  the  main 
bearings  ;  the  second  is  met  by  the  bed  casting  with  its 
lugs,  whereby  it  may  be  fastened  to  a  floor  or  a  small  brick 
foundation. 

The  cylinder  dimensions  and  speed  for  a  given  power  of 
engine  are  quantities  which  vary  so  with  the  quality  of  the 
fuel  used  and  its  temperature,  the  point  at  which  ignition 
takes  place,  and  other  items  which  cannot  all  be  previously 
known,  that  it  is  most  convenient  to  rate  the  engines  at  a 
nominal  horse  power  which  is  about  two-thirds  their  maxi- 


ENGINE   DETAILS   AND   THEIR   DB6IGN.  263 

mum  horse  power  when  working  under  the  best  conditions. 
For  a  four  cycle  engine  the  rule  for  finding  the  nominal 
horse  power  is  :— 

Multiply  together  the  square  of  the  C)  linder  diameter  in 
inches,  the  length  of  the  stroke  in  inches  and  the  number  of 
revolutions  per  minute  and  divide  the  product  by  28,000. 

For  example,  let  the  cylinder  diameter  be  2^  inches,  the 
.stroke  4  inches  and  the  revolutions  450  per  minute. 

(2j)'    X  4  X  450 

Then  -  —  =  .4018,  say  T4¥  nominal  horse  power. 

28,000 

In  applying  this  rule  to  two  cycle  engines  we  use  14,000 
as  a  divisor  in  place  of  28,000. 

The  rule  for  the  proper  speeds  of  engines  is  a  little  more 
complex  than  the  above,  as  it  involves  the  use  of  a  logarith- 
mic table  ;  for  a  four-cycle  engine  it  is  :— 

Divide  350  by  the  value  of  the  nominal  horse  power  raised 
to  the  ^Vth  power. 

Example.  Find  the  proper  speed  for  our  .4  nominal  horse 
power  engine  ? 

Log.  350  =  2.544063 

Log.  .4'-'  -^  1.60206  x  .21  1.916433 

Log.  ans.  =  2.627635  «  424.3  or 
say  425  revolutions. — Answer. 

For  two  cycle  engines  substitute  the  number  405  in  place 
of  350. 

The  ratio  between  the  length  of  the  stroke  and  the  cylinder 
diameter  varies  from  equality  in  small  engines  to  twice  the 
diameter  in  large  engines  of  foreign  make.  The  usual 
American  practice  is  to  make  the  stroke  one-fourth  greater 
than  the  cylinder  diameter  in  two  cycle  engines,  and  one- 
half  greater  in  four  cycle  types. 

The  volume  of  the   combustion  chamber  or  compression 


264  GAS   ENGINE   CONSTRUCTION. 

space  is  usually  one-third  of  the  total  cylinder  volume  meas- 
ured when  the  crank  is  on  the  outer  dead-center,  though 
modern  practice  has  often  reduced  it  to  T\  and  sometimes 
less.  In  estimating  this  the  spaces  over  the  valves  and  the 
passages  from  the  valves  to  the  cylinders  must  be  included. 

The  fly-wheel  of  a  gas  engine,  especially  on  the  four-cycle 
type,  must  store  in  itself  during  the  power-stroke  the  energy 
of  the  explosive  impulse  which  is  in  excess  of  that  which  is 
given  to  whatever  machinery  the  engine  drives,  and  then 
gradually  part  with  its  store  in  moving  the  engine  and  its 
attached  machinery  through  the  exhaust,  suction  and  com- 
pression strokes. 

In  engines  which  govern  by  the  hit-and-miss  method  the 
fly-wheels  of  the  engine  must  carry  it  along  for  four  or  six 
revolutions  when  the  load  is  very  light. 

Hence  it  is  seen  that  a  gas  engine  fly-wheel  must  have  con- 
siderable weight  in  its  rim  and  be  moving  at  a  high  speed  so 
that  the  momentum  shall  diminish  the  fluctuations  of  its 
velocity  to  an  amount  which  shall  be  so  small  that  it  will  not 
be  objectionable  for  the  purpose  for  which  the  engine  is  to 
be  used.  The  following  rule  for  the  weight  of  fly-wheels 
gives  the  weight  proper  to  the  kind  of  machinery  the 
engine  is  to  run. 

To  find  weight  of  rim  of  fly-wheels  multiply  together  the 
indicated  horse  power,  the  average  number  of  idle  strokes 
between  explosions,  and  one  of  the  constants  from  the  fol- 
lowing table ;  divide  this  figure  by  the  product  given  by 
multiplying  the  cube  of  the  number  of  revolutions  by  the 
square  of  the  mean  diameter*  of  the  fly-wheel  rim  measured 
in  inches. 


*  Mean  diameter  equals  the  sum  of  the  outer  and  inner  diameters 
divided  by  two. 


ENGINE   DETAILS   AND   THEIR   DliSIGN.  265 

TABLE  OF  FLY-WHEEL  CONSTANTS. 

For  pumping  and  ordinary  work,  556,416,000,000 

"  driving  machine  tools,  927,360,000,000 

"       looms,  etc.,  1,112,832,000,000 

"          "       dynamos,  etc.,  1,391,040,000,000 

"         "       spinning  machinery,  2,782,080,000,000 

These  constants  are  for  four-cycle  engines  ;  for  two-cycle  engines 

take  one-half  these  values.     If  it  is  desired  to  calculate  the  weight  by 

using  Brake  Horse  Power,  then  take  %  or  ^  of  these  values  for  four 

or  two-cycle  engines  respectively. 

As  the  above  rule  is  in  rather  a  cumbrous  form,  we  will 
repeat  it  in  a  diagrammatic  form  which,  though  not  as  ele- 
gant as  an  algebraic  formula,  will  perhaps  make  it  easier  for 
the  amateur  to  use. 

Weight  of  rim  in  pounds  = 

Indicated  H.P.  x  average  idle  strokes  x  constant  from  table 
(Revolutions  per  minute)3  x  (Mean  diameter  of  rim)2 

An  example  will  best  show  the  calculation. 

How  heavy  should  the  fly-wheel  rims  of  our  model  engine 
be  made  for  ordinary  purposes  ? 

Call  the  I.  H.  P.  T\. 

The  idle  strokes  when  running  at  full  power  will  be  3, 
viz.,  exhaust,  suction  and  compression.  If  we  wished  good 
regulation  at  half  load  we  would  use  the  number  7  on 
account  of  getting  an  impulse  once  in  8  strokes,  i.  e.,  in  4 
revolutions.  Some  designers  take  the  number  4  as  an  aver- 
age figure.  We  use  3  so  as  to  get  the  wheel  as  small  as 
is  advisable  for  the  amateur's  convenience. 

Multiplying  together  1\,  3,  and  the  first  constant,  556,416,- 
000,000,  gives  us  the  product  667,699,200,000.  Reserve  this 
until  needed  later. 

The  cube  of  the  number  of  revolutions  is  450x450x450 
=91,125,000. 


266  GAS   ENGINE   CONSTRUCTION. 

Mean  diameter  of  rim  is — +  ^   =—L=  12^  inches. 

2  2 

The  square  of  12^  is  156^,  or,  putting  it  decimally  for  con- 
venience, 156.25. 

The  product  of  91,125,0x30  times  156.25  equals  14,238,281,- 
250. 

Now  divide  our  first  product,  667,699,200,000,  by  this 
number,  14,238,281,250,  and  we  get  as  our  final  result 
46.89458,  or  say  47  pounds.  Dividing  this  into  two  parts 
gives  23^  pounds  for  the  rim  of  each  fly-wheel. 

The  size  of  the  wheel  rim  can  easily  be  calculated  by 
remembering  that  a  cubic  inch  of  cast  iron  weighs  very 
close  to  a  quarter  of  a  pound,  so  to  find  the  number  of  cubic 
inches  in  the  rim  we  multiply  the  weight  in  pounds  by  4, 
thus  :  23^x4=94  cubic  inches. 

For   convenience    we    may    now    assume    the    rim  to  be 

J 

straightened  out  into  a  rectangular  bar  whose  length  equals 
3.1416  times  the  mean  diameter,  or  3.1416x12^  inches  = 
39.27  inches.  Call  it  39^  inches. 

Now  since  the  cubic  contents  of  the  rim  are  to  be  94  cubic 
inches  and  we  have  its  mean  length  39^  inches,  it  is  obvious 
that  the  area  of  a  section  taken  vertically  across  the  rim 
will  be  equal  to  the  contents  divided  by  the  length,  or  94-=- 
394=2.395,  say  2$  square  inches.  So  for  width  and  depth 
of  rim  we  may  choose  any  two  numbers  whose  product 
equals  2f.  For  practical  purposes  we  might  take  i|-  inches 
wide  by  i  J  inches  deep,  which  would  give  nearly  the  above 
section,  or  2-g\  square  inches. 

To  save  turning  off  the  full  depth  of  the  rim  it  is  the  prac- 
tice to  form  a  shallow  edge  on  each  side  of  the  rim,  as  will 
be  seen  from  the  detail  drawing  on  page  166.  After  facing 
off  the  periphery  and  these  edges,  the  sunken  surface  and 


ENGINE   DETAILS   AND   THEIR  DESIGN.  267 

the  arms  are   finished  by  painting  to  match  the  bed  plate, 
etc. 

The  fly-wheel  arms  should  be  well  proportioned  so  as  not 
to  appear  clumsy  and  yet  be  strong  at  the  hub  to  take  the 
thrust  of  the  connecting  rod. 

In  a  single  cylinder  engine  of  this  kind  it  will  be  found 
desirable  to  balance  the  rapidly  moving  piston  and  connect- 
ing rod  by  weights  placed  opposite  the  crank  hubs  on  the 
fly-wheels.  While  no  engine  is  ever  perfectly  balanced  in 
this  way,  yet  it  is  the  nearest  approximation  that  is  simple 
and  practical. 

To  find  the  weight  of  the  counter-weights  add  together 
the  weight  of  the  crank  pin  with  its  cap  screws,  half  the 
weight  of  the  complete  piston  and  pin,  and  ^f  of  the  weight 
of  the  connecting  rod ;  multiply  this  sum  by  half  the  stroke 
and  divide  the  product  by  the  distance  from  the  center  of 
the  fly-wheel  to  the  center  of  gravity  of  the  balance  weight. 
Measure  all  the  weights  in  pounds  and  the  distances  in 
inches. 

Applying  this  rule  to  our  model  we  have  the  weight 

of  the  crank  pin  and  screws,  about       .         .  .50  pound. 

Half  weight  of  piston,  etc.,     .....      i.oo       " 
If  weight  of  connecting  rod,  ||  x  1.2  Ib     .         .  .97       " 


2.47 
Multiply  by  half  the  stroke  =  f  2 


Divide  by  distance  of  center  of  gravity    .         .         5*^4.94 

•99       " 

Call  the  answer  one  pound,  this  will  give  one-half  pound 
to  be  placed  on  each  wheel  and,  using  the  weight  of  cast 
iron  as  in  the  fly-wheel  calculation,,  will  require  2  cubic 
inches  of  cast  iron. 

The  size  of  main  shaft  in   engines  having  the  fly-wheels 


268 


GAS   ENGINE    CONSTRUCTION. 


outside  the  bearings  is  usually  taken  at  about  one-third  of 
the  cylinder  diameter.  In  our  model  engine  we  can  safely 
take  a  little  less.  One-third  of  2^  inches  is  |  inch,  so  we  take 
as  a  convenient  stock  size  f  inch. 

The  length  of  the  bearing  of  the  shaft  should  be  from  2 


FIG.  134. — GAS  ENGINE  BEARINGS. 

to  2\  times  the  diameter  of  the  shaft ;  we  have  used  a  little 
more  than  the  latter  figure  to  be  sure  of  a  good  rigid  bear- 
ing.    In  large,  high-speed  engines  the  bearings  should  have 
special  arrangements  to  keep  them  well  flooded  with  oil. 
In  Fig.  134  is  shown  an  excellent  design  for  this  purpose. 


ENGINE   DETAILS  AND   THEIR   DESIGN.  269 

Here  are  shown  the  cast  iron  housings  containing  the  bear- 
ing brasses.  Where  the  bearing  cap  is  removed  is  seen  a 
brass  ring,  which  hangs  loosely  on  the  shaft  and  whose  lower 
side  dips  into  a  reservoir  of  oil  in  the  bearing  pedestal  and 
when  in  action  carries  a  continuous  stream  to  the  top  of  the 
shaft.  At  the  left  of  each  pedestal  is  a  draw-off  cock  and  a 
gauge  glass  to  show  the  height  of  oil  in  the  reservoir.  The 
oil  cup  standing  on  a  pillar  at  the  top  is  to  oil  the  crank  pin 
and  will  be  described  later. 

The  diameter  of  the  crank  pin  should  be  one-fifth  greater 
than  that  of  the  shaft,  though  in  our  model  we  have  used 
the  same  size  so  as  to  save  the  amateur  the  cost  of  a  reamer 
for  the  crank  pin  brasses  alone. 

The  product  of  the  length  and  diameter  should  be  about 
equal  to  one-fifth  the  area  of  the  piston. 

The  crank  pin  is  also  an  important  part  to  keep  well  oiled. 
For  ordinary  work  a  good  screw-top  oil  cup  will  answer 
very  well,  but  when  an  engine  must  make  long,  uninter- 
rupted runs  some  other  method  must  be  used. 

Fig.  135  shows  another  view  of  the  same  bearings  given 
in  the  previous  cut.  A  sight-feed  lubricator  is  mounted  on 
a  neat,  steel  pillar  and  the  oil  from  it  is  delivered  by  a  tube 
to  a  wiper  attached  to  the  crank.  Thus  at  each  revolution 
a  small  quantity  of  oil  is  transferred  to  the  interior  of  the 
crank  and  flows  through  the  hole  to  the  bearing  surfaces. 

This  device  could  be  applied  to  our  model  engine  by  drill- 
ing the  crank  pin  as  shown  and  also  drilling  one  of  the 
cap  screws  and  arranging  on  its  head  a  piece  of  thin  tubing 
shaped  like  a  stub  pen  so  that  it  will  catch  the  drop  of  oil 
and  throw  it  into  the  hole  in  the  pin. 

The  connecting  rod  should,  in  larger  engines,  be  made 
larger  at  the  crank  pin  end  than  at  the  piston  end.  Its  mean 
diameter  may  be  taken  as  J  of  the  cylinder  diameter  when 


2/0 


GAS   ENGINE   CONSTRUCTION. 


it  is  twice  the  length  of  the  stroke,  and  is  proportionally 
larger  up  to  one-third  of  the  cylinder  diameter,  when  it 
is  three  times  the  length  of  the  stroke. 

The  length  of  the  bearing  surface  of  the  piston  pin  should 
be  the  same  as  that  of  the  crank  pin,  and  the  product  of  its 
length  and  diameter  should  equal  one-tenth  of  the  piston 
area. 


FIG.  135. — CRANK  PIN  OILER. 

In  our  model,  ^  of  the  piston  area,  4.91  square  inches,  is 
.49 ' ,  or  say  £  square  inch,  the  piston  pin  bearing  is  ^  inch  in 
diameter,  its  length  is,  therefore,  i  inch. 

The  length  of  the  trunk  piston  should  not  be  less  than  I J 
times  its  diameter.  In  the  model  the  piston  length,  3T76- 
inches,  is  -J  inch  longer  than  i^  x  2j  =  3T5F  inches,  nearly. 

Larger  pistons  for  heavier  service  would  be  made  of  a 


ENGINE   DETAILS   AND   THEIR   DESIGN.  2/L 

si:  g-le  casting  without  .the  steel  shell  and,  instead  of  the 
asbestos  packing,  will  require  three  or  four  spring  piston 
rings  set  in  grooves  turned  in  the  body  of  the  piston  near 
the  rear  end.  In  designing  cylinders  of  steel  tubing  of 
larger  sizes  than  2\  inch  diameter  the  wall  of  the  cylinder 
should  be  taken  proportionately  thicker,  but  it  will  not  be 
necessary  to  have  a  greater  thickness  than  -J  inch,  as  the 
tubing  is  not  listed  above  4  inches  diameter.  The  depth  of 
the  water  jacket  is  -^  the  cylinder  diameter.  It  should 
extend  along  the  cylinder  to  a  point  a  little  beyond  where 
the  piston  exposes  the  cylinder  wall  to  the  hot  gases.  In 
larger  engines  the  cylinder  head  should  be  cast  hollow  so  as 
to  be  a  continuation  of  the  water  jacket  and  it  is  also  desir- 
able to  water-jacket  the  exhaust  valve  casing  so  that  it  will 
not  become  too  hot  and  the  valve  stem  cut  into  its  guide. 

The  thickness  of  the  cylinder  head  should  be  about  y1^  of 
the  cylinder  diameter,  this  will  make  it  strong  enough  to 
support  the  valves. 

In  these  small  engines  the  cylinder  head  is  often  fastened 
on  with  six  iron  screws,  as  in  our  model. 

To  find  the  size  of  the  screw  for  this  type  of  engine  it  will 
be  sufficient  to  take  it  as  -^  the  cylinder  diameter  when  six 
screws  are  used.  Should  the  construction  of  a  different  type 
be  contemplated,  involving  higher  pressures,  the  designer  is 
recommended  to  study  some  of  the  recent  works,  mentioned 
in  the  next  chapter,  which  treat  the  subject  more  fully. 

The  diameter  of  the  inlet  port  should  be  31^  per  cent,  of 
the  cylinder  diameter,  and  the  diameter  of  the  exhaust  port 
should  be  35  per  cent,  of  the  same.  The  lift  of  the  valves 
must  be  at  least  equal  to  one-quarter  of  their  diameters,  and 
they  should  have  stems  long  enough  to  allow  a  little  more, 
to  compensate  for  any  delay  in  action  or  rebound  from  the 
washer  striking  the  valve  stem  guide. 


2/2  GAS   ENGINE   CONSTRUCTION. 

The  diameter  of  the  threaded  and  keyed  ends  of  the  side 
rods  may  be  taken  as  J  of  the  cylinder  diameter  and  the 
maximum  diameter  of  the  rods  at  the  shoulders  is  half  as 
much  again. 

As  to  the  governor,  in  a  larger  engine  this  may  be  enlarged 
proportionately  and  have  a  stiffer  spring.  There  are  other 
methods  of  governing  which  may  be  considered  preferable 
under  different  conditions,  they  may  be  classified  as  follows: 

f  i.  Closing  gas  inlet. 

2.   Opening  or  closing  exhaust. 
Hit-or-miss.  1 

i  3.  Shutting  off  igniter. 

[4.  Uncoupling  valve  shaft. 

f5.  Throttling  gas  supply. 

Variable  impulse.  -{  6.  Throttling  charge  of  gas  and  air. 
[_  7.  Varying  point  of  ignition. 

The  hit-or-miss  methods  give  a  complete  and  unvarying 
charge  to  the  cylinder  whenever  required,  but  omit  any 
impulse  whatever  at  other  times,  so  that  at  light  loads  the 
engine  operates  with  irregularly  timed  impulses,  at  rather 
heavy  loads  there  are  a  number  of  successive  impulses  with 
an  occasional  miss  and  at  full  loads  there  is  an  explosion  at 
every  stroke  and  the  engine  runs  the  steadiest. 

With  the  variable  impulse  methods  there  is  an  explosion 
at  every  stroke,  but  its  force  is  varied  by  the  governor,  as 
explained  later.  This  results  in  a  much  more  even  running 
of  the  engine  and  with  two  or  more  cylinders  is  adequate  to 
the  exacting  demands  of  electric  lighting  service. 

The  governor  illustrated  in  Figs.  6  and  8  is  a  good  exam- 
ple of  method  i.  As  there  explained,  the  valve  remains 
closed,  except  when  running  at  normal  speed,  then  it  is  ope- 
rated by  the  cam  at  the  proper  interval  in  the  cycle. 


ENGINE   DETAILS   AND   THEIR   DBSIGN.  273 

The  2d  method  is  partly  illustrated  by  our  model  engine. 
Keeping  the  valve  shut  will  retain  the  burnt  gases  which 
will  be  compressed  on  the  instroke  but  will  push  the  piston 
out  again,  so  no  power  is  lost  except  by  the  heat  due  to  com- 
pressing the  gases  being  carried  off  by  the  water  jacket. 
Retaining  the  valve  in  an  open  position  will  simply  allow 
the  exhaust  gases  to  be  drawn  in  and  out  again  as  long  as 
the  valve  stays  open. 

The  3d  method  is  a  wasteful  one  unless  used  in  a  specially 
devised  engine,  in  which  there  can  be  no  charge  drawn  in 
unless  an  explosion  has  occurred. 

Method  4  is  a  very  good  one.  The  shaft  is  unclutched 
from  the  gear  by  the  governor,  so  as  to  stop  it  when  holding 
the  exhaust  valve  open,  thus  doing  away  with  the  compres- 
sion and  expansion  of  the  confined  gases  and  diminishing  as 
well  the  wear  of  the  cams,  valve  gear,  igniter,  etc. 

The  5th  method  is  one  in  which  a  small  variation  in  the 
proportions  of  gas  and  air  in  the  charge  will  make  a  large 
difference  in  the  power  produced.  It  is  not  an  economical 
method,  as  a  given  amount  of  gas  will  give  its  maximum 
force,  only  when  mixed  with  a  definite  amount  of  air.  On 
this  account  the  hit-and-miss  methods  have  been  so  long  in 
vogue,  as  they  use  an  unvarying  proportion  of  charge. 

Method  6  unites  both  economy  and  good  regulation.  It 
keeps  the  gases  of  the  charge  mixed  in  their  most  suitable 
proportions  and  admits  them  in  an  amount  dependent  on 
the  work  to  be  done.  This  method  has  been  applied  to  the 
largest  engines. 

The  /th  method  has  made  its  appearance  recently  in  con- 
nection with  gasoline  motor  vehicles.  It  is  not  used  with  a 
governor  to  maintain  a  constant  speed  but  to  vary  the  speed 
by  hand  within  wide  limits,  say  from  150  or  200  to  1,500 
revolutions  per  minute.  It  is  only  done  with  the  electric 


2/4 


GAS   ENGINE   CONSTRUCTION. 


mode  of  ignition  by  moving  the  circuit  closing-  spring  around 
the  center  of  the  larger  gear. 

We  will  now  take  up  the  subject  of  igniters.  As  the 
student  has  seen,  it  is  necessary  that  the  mixture  of  gas  and 
air  should  have  a  combustion  started  in  it  at  the  proper 


FIG.  136. — DIRECT  FLAME  IGNITER  WITH 
VALVE. 

moment  of  the  cycle.     The  various  methods  of  accomplish- 
ing this  firing  of  the  charge  we  may  classify  as  follows : 


Direct. 


Flame. 


(  Valve. 
'  Suction. 
f  Tube. 
-{  Cone. 
[Rod. 


ENGINE   DETAILS   AND   THEIR  DESIGN.  2/5 

Strike. 


f  Primary. 

b      ,-  '  Wipe. 

Spark.  ^  r 


Secondary.  ) 

(  Toothed  interrupter. 


The  direct  flame  method  is  used  very  little  at  present. 

The  valve  form  consists  in  having  a  chamber  in  a  sliding 
valve  as  represented  by  the  cavity  r  in  valve  B,  Fig.  136. 
A  small  jet  of  gas  admitted  through  a  is  ignited  by  the  flame 
c  at  the  port  d.  The  valve  is  now  moved  so  that  one  of-  the 
ports  of  its  flame  cavity  is  opposite  an  opening  into  the 
cylinder  and  the  flame  of  the  remaining  gas  and  air  burning 
in  the  cavity  is  communicated  to  the  charge  and  explosion 
ensues. 

The  suction  form  of  flame  igniter  is  only  applicable  to 
engines  of  Class  I.  About  the  middle  of  the  cylinder  is  an 
opening  in  the  cylinder  wall  provided  with  a  small  steel 
shutter  hanging  loosely  over  its  inner  end.  A  flame 
impinges  on  its  outer  end.  When  the  piston  moves  forward, 
drawing  in  the  charge,  it  uncovers  the  ignition  port,  the 
flame  is  sucked  in,  the  charge  explodes  and  the  impact  closes 
the  little  steel  shutter  which  prevents  escape  of  the  force  of 
the  expanding  gases. 

The  hot  tube  is  one  of  the  best  known  methods  of  indirect 
flame  ignition. 

When  first  brought  into  use  it  was  thought  desirable  to 
have  its  action  under  the  control  of  a  valve.  Fig.  137  shows 
how  this  was  accomplished.  At  C  is  the  tube  surrounded  by 
flame  from  a  Bunsen  burner,  which  is  attached  at  the  lower 
rear  part  of  the  asbestos-lined  chimney.  At  A  is  the  com- 
bustion chamber  of  the  cylinder  ;  at  B  is  what  is  called  the 
timing  valve,  which  is  operated  from  a  cam  shaft  through 
the  bell  crank  E  and  the  adjusting  nut  F.  The  spring  D 


2;6 


GAS   ENGINE   CONSTRUCTION. 


holds  the  valve  to  its  seat  against  the  force  of  the  compres- 
sion. 

When  the  proper  moment  comes  the  valve  is  drawn  back 
and  the  compressed  mixture  rushes  in  and  part  way  up  the 
tube,  then  the  red  heat  of  the  tube  fires  the  gases  in  it,  the 


FIG.  137. — HOT  TUBE  IGNITER  WITH  TIMING  VALVE. 

flame  rushes  back    to  the    cylinder  and    ignites   the  whole 
mass. 

Further  experience  with  hot  tube  igniters  developed  the 
fact  that  a  timing  valve  \vas  not  always  necessary.  The 
regulation  could  be  effected  by  varying  the  distance  that 
the  fresh  charge  must  travel  up  the  tube  before  reaching  the 
igniting  surface. 


ENGINE   DETAILS   AND   THEIR   DESIGN. 


277 


How  this  is  done  is  illustrated  in  Fig.  138.  Here  A  is  the 
cylinder  space,  B  the  ignition  port  and  C  the  Bunsen  burner, 
which  is  fastened  to  the  chimney  by  a  swivel  at  D. 

The  chimney  is  capable  of  being  moved  up  or  down  on 
the  post  so  as  to  vary  the  place  of  redness  of  the  tube.  A 


FIG.  138. — HOT  TUBE  IGXITER. 

further  small  adjustment  can  be  obtained  by  swiveling  the 
burner  tube,  at  D. 

The  principle  of  action  is  simply  that  the  higher  the  flame 
is  up  the  tube  the  farther  the  fresh  charge  will  have  to  travel 
and  compress  the  burnt  gases  ahead  of  it  before  it  reaches 
the  igniting  port  and  the  later  the  ignition  will  occur. 


278  GAS   ENGINE   CONSTRUCTION. 

Iron  tube  is  commonly  used  for  these  igniters,  but  as  they 

burn  out  soon  and  break  it  is  better  to  use  a  tube  of  nickel. 

i 

Platinum  or  porcelain  tubes  are  also  used. 

The  cone  and  rod  igniters  are  both  adapted  for  use  with 
petroleum  engines. 

It  is  a  property  of  a  compressed  mixture  of  petroleum 
vapor  and  air  that  it  ignites  readily  by  contact  with  a  body 
which  is  not  quite  at  a  red  heat. 

In  actual  engines  a  hollow  casting  is  fastened  to  the  rear 
of  the  cylinder  and  is  unprovided  with  a  water-jacket,  but 
is  guarded  by  a  cast  iron  hood  provided  with  a  short  chim- 
ney and  damper  above  and  a  larger  opening  below. 

Before  starting  the  engine  a  large  oil  or  gas  burner  is 
lighted  and  placed  below  the  hood  and  the  damper  opened 
so  that  the  flame  will  surround  the  hollo w  cone.  When  the 
cone  is  hot  enough  the  engine  is  started,  and  as  soon  as  it  is 
running  at  full  speed  the  burner  is  removed  and  extinguished. 
The  damper  is  now  closed  enough  to  keep  the  cone  at  a 
proper  temperature,  for  it  will  be  receiving  heat  from  the 
explosions  within  and  losing  heat  by  radiauon  and  by  ths 
air  current  up  through  the  hood 

To  aid  in  receiving  heat  from  the  hot  gases  in  the  cylinder 
the  cone  may  have  ribs  cast  on  its  interior,  which  project 
inwardly  and  by  spraying  the  charge  of  petroleum  upon 
them  these  ribs  perform  the  triple  function  of  vaporizer,  heat 
conductor  and  igniter. 

The  rod  method  consists  in  having  a  small  bar  of  nickel 
located  within  the  cylinder  over  a  port  by  which  a  flame  can 
be  introduced  to  heat  the  rod.  The  port  is  then  closed  and 
the  engine  operates  the  same  as  with  the  cone. 

A  spiral  of  platinum  wire  or  a  grating  of  the  same  have 
also  been  used  in  this  way. 

When  the  governing  is  by  the  hit-and-miss  method  these 


ENGINE   DETAILS   AND   THEIR   DESIGN.  2/Q 

hot  metal  igniters  will  not  work  satisfactorily  unless  there  is 
sufficient  load  on  the  engine  to  make  the  explosions  frequent 
enough  to  keep  the  igniter  from  cooling  too  much. 

The  first  of  the  electrical  methods  is  practically  the  same 
as  is  used  for  gas  lighting  in  private  residences.  The  circuit 
breaker  is  connected  in  series  with  a  battery  and  spark  coil. 
When  the  circuit  is  completed  the  current  passes  and  mag- 
netizes the  iron  wire  core  of  the  coil.  On  breaking  the  cir- 
cuit the  instant  collapse  of  the  magnetic  lines  of  force  into 
the  iron  core  creates,  by  the  well-known  phenomenon  of 
induction,  an  electric  pressure  in  the  circuit  greatly  in  excess 
of  that  due  to  the  battery  and  prolongs  the  flow  of  current 
for  a  considerable  distance  through 
the  air  between  the  rapidly  sepa- 
rating contacts. 

On   account   of    the    rapid   run- 
ning of   gas  and  gasoline  engines 
the  coils  suitable  for  gas  lighting     ^  I^_SpMX  ColL. 
are   not   well    adapted    to    engine 

ignition  as  their  long  cores  require  an  appreciable  time  to 
become  fully  magnetized. 

To  make  the  coil  quicker  in  action  a  short  form  must  be 
used.  Fig.  139  shows  a  coil  of  this  kind.  A  battery  of  low 
internal  resistance  should  be  employed. 

The  circuit  breaker  inside  the  cylinder  is  variously  con- 
structed by  different  makers,  but  all  have  practically  the 
same  parts — one  stationary  and  insulated  electrode  and  one 
movable  electrode  connected  to  some  rotating  or  recipro- 
cating part  of  the  engine,  so  that  it  shall  make  and  break  con- 
tact with  the  fixed  electrode  at  the  proper  time.  An  igniter 
using  the  "  strike  "  method  is  described  and  illustrated  on 
page  26  and  Fig.  7.  The  sparking  surfaces  must  be  of 
platinum  or  a  special  hard  alloy. 


280 


GAS   ENGINE   CONSTRUCTION. 


The  electric  circuit  is  from  battery  through  the  spark  coil 
to  the  engine  frame,  thence  from  the  insulated  electrode 
back  to  the  battery. 

The  wipe  spark  is  electrically  the  same  as  the  strike 
method  but  the  contacts  have  a  rubbing  action  instead  of 
being  merely  pressed  together. 

In   Fig.  140  is  shown  an  arrangement  of  this  kind.     The 

insulated  fixed  electrode  is  shown 
with  a  spring  point  projecting 
upwards  so  as  to  engage  a 
stirrup  attached  to  the  rear  of 
the  piston.  This  is  done  at  the 
inner  end  of  the  stroke  so  that 
as  the  piston  moves  forward  the 
spring  will  be  compressed  until 
its  point  is  released,  breaking  the 
circuit  and  producing  the  spark. 
This  device  has  been  selected 
as  a  lesson  to  the  designer  in 
what  to  avoid  in  this  class  of 
igniter.  We  will  point  out  de- 
fects in  this  form  and  suggest 
changes  in  its  arrangement. 
First,  the  coiled  spring  will  not 
last  long  under  the  action  of  the 
hot  gases.  Second,  the  time  of 
the  spark  will  be  delayed  later  than  it  should.  Third,  there 
is  no  means  of  regulating  the  time  of  the  spark.  Fourth, 
the  spring  or  stirrup  may  get  hot  enough  to  act  as  an 
igniter  like  the  nickel  rod  mentioned  on  page  278.  Fifth, 
on  a  four  cycle  engine  a  switching  device  would  be  needed 
to  turn  off  the  current  at  alternate  strokes. 

All  this  could  be  avoided  and  better  results  secured  by 


FIG.  140. — WIPE  SPARK 
DEVICE. 


ENGINE   DETAILS   AND   THEIR    DESIGN.  28 1 

arranging  a  rotating  electrode  which  should  connect  with  a 
springy,  insulated  electrode  once  in  each  cycle,  or  by  a  little 
more  ingenuity  the  spring  could  be  entirely  outside  the 
cylinder. 

The  time  of  ignition  could  be  adjusted  by  varying  the 
relative  angular  position  of  the  rotating  electrode  and  its 
driving  gear. 

The  fourth  objection  is  one  which  needs  attention  as  it 
has  often  been  overlooked*  The  remedy  is  to  keep  the  elec- 
trodes as  cool  as  possible  and  this  is  conveniently  done  by 
placing  them  just  within  the  inlet  port  so  the  fresh  charge 
will  blow  past  them  at  each  admission.  This  point  applies 
with  equal  force  to  all  kinds  of  electric  igniters.  It  is  illus- 
trated in  Fig.  7,  page  27,  where  the  electrodes  are  seen  in 
the  port  opening  into  the  cylinder  just  over  the  inlet  valve. 

A  very  desirable  point  in  engine  design  is  to  place  oppo- 
site the  igniter  a  screw  plug  which  can  be  removed  and  the 
spark  observed  while  turning  the  engine  by  hand,  the  gas  of 
course  being  shut  off. 

The  methods  of  ignition  by  a  secondary  or  "jump  "  spark 
require  less  mechanism  on  the  engine.  The  principle  is 
that  when  a  rapidly  interrupted  current  is  sent  'through  the 
primary  coil  of  a  Ruhmkorff  or  induction  coil,  it  will  pro- 
duce in  its  secondar}'  coil  a  current  of  sufficient  force  to 
jump  the  space  between  the  two  fixed  and  insulated  elec- 
trodes. 

We  will  riot  describe  the  vibrator  method  here  as  it  has 
been  treated  of  in  Chapters  XX  and  XXIT. 

The  toothed  interrupter  is  simply  a  wheel  on  the  valve 
cam  shaft  provided  with  one  or  more  teeth  which  touch  a 
contact  spring,  and  the  spring  and  teeth  are  connected  so 
as  to  take  the  place  of  the  vibrator  on  the  coil. 

This   arrangement  is    used  on  automobile  motors  where 


282  GAS   ENGINE  CONSTRUCTION. 

the  speeds  are  so  high  that  the  vibrator  springs  would  not 
act  quickly  enough,  and  also  by  shifting  the  contact  spring 
around  the  wheel  the  speed  is  changed  as  already  explained 
under  the  head  of  governors. 

One  more  ignition  arrangement  deserves  mention.  It  is 
the  one  used  in  the  Diesel  motor  and  consist  in  compress- 
ing the  air  to  so  high  a  temperature  as  to  ignite  the  fuel 
when  introduced. 

In  closing  we  will  speak  of  the  silencing  and  disposal  of 
the  exhaust.  The  whole  point  is  to  get  the  exhaust  down 
to  atmospheric  pressure  gradually.  This  can  be  done  by 
gradually  increasing  the  size  of  the  exhaust  pipe,  by  placing 
expansion  chambers  or  mufflers  on  the  pipe,  or  by  allowing 
it  to  escape  through  a  number  of  small  openings. 

The  rule  for  volume  of  muffler  is  to  take  3!  times  the 
product  of  the  square  of  the  piston  diameter  multiplied  by 
the  stroke. 

Applied  to  our  model,  3.5  x  2-53  x  4  =  87-^  cubic  inches, 
Answer. 

This  is  about  equivalent  to  4-^-  times  the  piston  displace- 
ment, so  a  piece  of  2\  inch  iron  pipe,  18  inches  long  will  be 
suitable.  The  ends  should  be  provided  with  reducers  for 
inlet  and  outlet  of  the  exhaust.  It  is  preferable  when  it  can 
conveniently  be  done,  to  make  the  outlet  pipe  from  the 
muffler  a  size  larger  than  the  inlet. 


CHAPTER     XXV. 


VERTICAL   ENGINE. 

With  a  slight  modification  of  some  of  the  parts  this  en- 
gine can  be  constructed  in  the  upright  style  as  shown  in 
Fig.  141.     This  may  be  found  advisable  where  floor  space 
is    limited.      The    parts  which   re- 
quire   modification     are    the    bed 
plate,  bearings,  side  rods  and  con- 
tacts.    Two  entirely  new  parts  will 
have    to    be    added,    consisting    of 
a  small  bracket   and  spring  which 
are  required  to  keep  the  governor 
in    an    upright    position.      Several 
engines    have    already    been    built 
from    this    design    and    work  very 
successfully. 

Fig.  142  shows  the  design  of  the  bed  plate,  the  pattern  of 
which  is  easier  to  construct  than  is  that  of  the  horizontal 
style. 

It  will  be  noticed  that  the  top  of  the  bed  plate  is  made 
quite  thick.  This  is  to  give  a  good  long  hole  for  the  cap 
screws  by  which  the  bearings  are  held  down.  The  same 
instructions  given  in  Chapter  VI.  are  to  be  followed  in 
building  up  this  pattern. 

The  only  finish  required  on  the  casting  is  to  plane  or  file 
off  the  two  top  surfaces  on  Avhich  the  bearings  are  to  rest. 

As  the  bearings  and  side  rods  of  this  style  of  engine  have 


FIG.  141. — UPRIGHT 
STYLE  GAS  ENGINE. 


284 


GAS    ENGINE    CONSTRUCTION. 


to  withstand    a   considerable    side    thrust  at  each  impulse, 
they  must  necessarily  be  made  correspondingly  stronger. 


FIG.  142. — BED  PLATE  FOR  UPRIGHT  ENGINE. 

Fig.  143  shows  the  sizes  of  the  various  parts  of  the  bear- 
ings.    It  will  be  noticed  that  both   bearings  are  exact  dupli- 


VERTICAL   ENGINE.  §  285 

cates,  with  the  exception  that  the  one  which  is  located  on 
the  valve  gearing1  side  of  the  engine  has  a  small  hub  or  boss 
cast  on  to  hold  the  gear  stud,  and  also  a  small  flat  projec- 
tion near  the  shaft,  to  which  is  screwed  the  fiber  block  hold- 
ing the  contacts. 

To  save  unnecessary  work  only  one  pattern  need  be  made. 

The  small  boss  for  the  gear  stud  and  the  projection  for 
the  fiber  block  can  be  attached  to  the  pattern  by  small  brads 
after  it  is  finished  and  shellacked.  The  foundryman  can  then 
be  instructed  to  make  one  casting  with  these  parts  in  posi- 
tion, and  the  second  casting  after  they  have  been  removed. 

Another  plan  is  to  fasten  these  parts  securely  to  the  pat- 
tern and  then  remove  them  from  one  of  the  finished  cast- 
ings by  filing  or  machining. 

The  dimensions  given  in  Fig.  143  are  finished  sizes. 
When  building  up  the  pattern  allowance  should  be  made 
for  finish  on  the  bottom  and  top  and  for  facing  off  both  ends 
of  the  bearing,  together  with  the  necessary  shrinkage  of  the 
casting. 

As  the  size  for  the  finished  hole  for  the  shaft  is  to  be  £ 
inch,  the  pattern  can  be  made  to  core  out  this  hole  to  f  inch 
if  desired.  This  will  save  considerable  work  in  drilling  out 
and  boring  the  casting. 

The  mode  of  procedure  in  boring,  facing  and  finishing 
these  castings  will  be  somewhat  different  from  that  of  the 
horizontal  bearings  described  in  Chapter  XI.  because  of  their 
difference  of  arrangement  and  shape. 

In  the  former  case  the  casting  was  chucked  by  the  hub  of 
the  bearing,  and  the  hole  for  the  shaft  finished  and  reamed. 
This  hole  was  then  placed  on  the  pin  of  the  angle  plate,  and 
the  boss  drilled  and  reamed  for  the  side  rods,  after  which 
the  casting  was  swung  around  on  the  pin  and  the  bottom  of 
the  bearing  faced  off. 


286 


GAS   ENGINE   CONSTRUCTION. 


CAST  IRON 

MAKE  ONE 


36  BRASS  SCREW 

V'2     LONG 
BRASS  HEX,   NUTS 


CAST  IRON 

MAKE  ONE 

FIG.   143. — BEARINGS  FOR  UPRIGHT  ENGINE. 


VERTICAL   ENGINE. 


287 


In  the  case  of  the  upright  bearing,  the 
side-rod  boss  and  the  base  of  the  casting 
being  diametrically  opposite  each  other, 
there  will  not  be  sufficient  space  between 
the  back  of  the  angle  plate  and  the  pin  to 
allow  the  casting  to  be  thus  placed.  The 
first  operation  will  be  to  catch  the  side- 
rod  boss  in  the  jaws  of  the  chuck  and  face 
off  the  bottom  of  the  casting. 

See  that  the  boss  runs  true  in  the  chuck. 
In  this  operation  the  important  thing  to 
be  observed  is  to  have  both  castings  faced 
off  equally,  so  that  the  distance  from  the 
hub  of  the   bearing,  or  the  center   of  the     ^ 
hole  to  the  bottom  of  the  casting,  will  be  |  £ 
the  same  in  both  cases.     For  the  next  opera-  ^  ™ 

O   _| 

tion  remove  the  chuck  from  the  lathe  head     % 

r 

and  place  the  face  plate  in  position.  Put 
the  finished  surface  of  the  bottom  of  the 
bearing  against  the  face  plate,  first  inserting 
a  thickness  of  newspaper  between  (see  page 
137).  Hold  the  casting  in  position  tempo- 
rarily by  bringing  up  the  back  center  of 
the  lathe  against  the  side-rod  boss.  The 
casting  can  now  be  bolted  lightly  to  the  face 
plate  and  the  lathe  revolved  a  few  times  by 
hand  to  see  that  the  boss  runs  true.  If  not 
true  a  light  tap  with  a  small  hammer  will 
shift  the  position  of  the  casting  on  the  face 
plate,  and  a  few  trials  will  bring  it  to  the 
proper  position. 


1*4/4  J 


FIG.  144. — SIDE 
The  bolts  should  then  be  tightened  up  RODS  FOR  UPRIGHT 

to    clamp    the   casting   firmly   to  the  face  ENGINE. 


288 


GAS    ENGINE    CONSTRUCTION. 


plate,  while  the  hole  for  the  side  rods  is  drilled,  bored  and 
reamed  and  the  end  of  the  boss  faced  off. 

After  finishing  the  holes  for  the  side  rods  the  angle  plate 
is  attached  to  the  face  plate  of  the  lathe  and  the  bearing  set 
upright  on  the  shelf  of  the  angle  plate  and  clamped  there. 
The  angle  plate  is  now  to  be  adjusted  to  the  proper  height 
to  bring  the  casting  in  position  to  bore  and  ream  the  hole 
3,, y,,  for  the  shaft.  One  end 

-rK 


of  the  bearing  can  be 
faced  off  at  this  time,  and 
the  opposite  end  is  after- 
ward faced  by  placing  the 
bearing  on  a  f-inch  man- 
drel between  the  lathe 
centers.  After  the  angle 
plate  is  set  for  one  cast- 
ing, it  must  not  be 
loosened  from  the  face 
plate  until  the  second 
bearing  has  been  finished, 
else  the  height  of  the 
hole  for  the  shaft  will 
not  be  exactly  the  same 
distance  from  the  bottom 


STEEL  SDRING 

MAKE  ONE 


FIG.  145. — BRACKET  AND  SPRING 
FOR  GOVERNOR. 


of  the  bearing,  and  in  consequence  the  holes  will  not  "  line  up" 
properly.  The  only  adjustment  necessary  for  the  second 
casting  is  to  move  it  forward  or  back  on  the  shelf  of  the 
angle  plate  until  the  hub  of  the  bearing  runs  true  when  the 
lathe  is  revolved.  In  both  cases  the  hub  of  the  bearing  must 
be  parallel  with  the  bed  of  the  lathe. 

We  have  not  deemed  it  necessary  to  illustrate  these  oper- 
ations, as  they  are  almost  identical  with  those  of  the  horizon- 
tal type  of  bearing  which  is  fully  illustrated  and  described 


VERTICAL   ENGINE.  289 

In  Chapter  XL,  the  only  difference  being  in  the  manner  of 
holding 'the  castings,  and  this,  we  are  sure,  will  be  readily 
understood  by  the  reader. 

The  contacts,  as  will  be  noted  on  referring  to  Fig.  143, 
must  have  a  different  bend  at  the  bottom  from  those  de- 
scribed on  page  231.  This  is  so  clearly  shown  that  farther 
description  is  unnecessary. 

In  the  horizontal  engine  the  side  rods  are  turned  from 
f-inch  machinery  steel  and  are  of  equal  diameter  at  each 
end.  In  the  vertical  style  the  rods  are  turned  from  i-inch 
machinery  steel  and  the  diameter  is  smaller  at  the  top. 

After  the  ends  have  been  turned  down  to  their  proper 
sizes,  the  central  portion  is  tapered  as  shown  in  Fig.  144. 
If  the  work  is  done  in  a  screw-cutting  lathe  the  tail  stock  of 
the  lathe  is  set  over  far  enough  to  give  the  proper  taper.  If 
done  on  a  lathe  with  a  plain  slide  rest,  the  latter  must  be 
given  the  proper  angle  with  the  bed  of  the  lathe  to  give  the 
required  result. 

The  cylinder  supports  described  in  Chapter  XL  will  not 
be  needed  in  this  style  of  engine. 

In  order  to  adapt  the  same  design  of  governor  described 
in  Chapter  XIX.  it  will  be  necessary  to  add  some  attach- 
ment which  will  cause  the  governor  roller  to  drop  into  the 
depression  filed  in  the  valve  rod,  corresponding  to  its  drop 
by  gravity  in  the  horizontal  type. 

This  is  accomplished  by  the  bracket  and  spring  shown  in 
Fig.  145.  This  bracket  fits  on  the  valve-rod  bearing. 

The  screws  which  fasten  the  bearing  to  the  cylinder  collar 
also  pass  through  the  two  holes  in  the  thin  portion  of  the 
bracket.  The  projection  of  the  bracket  is  thus  held  just 
below  the  lower  end  of  the  governor  lever,  and  the  flat  bent 
steel  spring  between  them  gives  the  proper  tension  to  the 
governor  mechanism. 


290  GAS   ENGINE   CONSTRUCTION. 

The  spring  is  held  in  place  by  the  No.  6-32  screw  tapped 
into  the  bracket  at  the  place  indicated  in  the  cut.  The  tension 
of  the  spring  can  be  varied  by  a  slight  opening  or  closing  of 
the  bend. 


CHAPTER    XXVI. 

ANNOTATED    BIBLIOGRAPHY    OF    THE   PRINCIPAL   GAS   ENGINE 

BOOKS   PUBLISHED    IN   THE    ENGLISH 

LANGUAGE. 

Allen,  James  T. 

DIGEST  OP  U.  S.  AUTOMOBILE  PATENTS  FROM  1789  TO  JULY  i, 

1899.     472  pi.     713  pp.     Washington.     1900. 

Classifies  horseless  vehicles  according  to  their  motive  power  being 
either  springs,  steam,  gas,  air  or  electricity.  Also  sections  on  gear- 
ing, traction  engines,  etc.  Contains  about  200  drawings,  descriptions 
and  claims  of  patents  on  gas-propelled  carriages. 

Beaumont,  W.  Worby. 

MOTOR  VEHICLES  AND  MOTORS  ;  THEIR  DESIGN,  CONSTRUCTION 
AND  WORKING  BY  STEAM,  OIL  AND  ELECTRICITY.     457  illus. 
636  pp.     Westminster  and  Philadelphia.     1900. 
An   exhaustive  treatise   on  automobiles  and  motor  cycles  of  the 
principal  American  and  foreign  builders.     Its  thirty-nine   chapters 
are  replete  with  details  and  descriptions. 

Bramwell,  Charles  C. 

THE  CONSTRUCTION  OP  A  GASOLINE  MOTOR  VEHICLE.     86  illus. 

149  pp.     New  York.      1901. 

The  first  part  of  this  work  describes  the  principles  of  operation  of 
gasoline  engines,  methods  of  mixing  the  fuel  and  air,  modes  of  igni- 
tion, relative  efficiency  of  transmission  devices,  etc.  The  remainder 
of  the  book  gives  a  description  in  detail  of  a  gasoline  engine  and 
vehicle  for  it. 


2Q2  GAS   ENGINE   CONSTRUCTION. 

Clerk,  Dugald. 

THE  GAS  AND  OIL  ENGINE.     6th  ed.     228  illus.     568  pp.     Lon.- 
don.      1896.  • 

A  historical  sketch  is  followed  by  the  classification  and  thermody- 
namics of  the  gas  engine.  Various  types  of  engine  are  illustrated  and 
explained.  Oils  and  oil  engines  are  separately  treated.  The  book 
closes  with  chapters  on  gases  and  their  analysis.  A  list  of  British 
gas  and  oil  engine  patents  is  appended. 


Colliery  Engineer  Co.  (The) 

AN  ELEMENTARY  TREATISE  ON  THE  GAS  ENGINE.  341  illus. 
712  pp.  5vols.  Scranton,  Pa.  1899. 

This  valuable  and  practical  work  is  prepared  for  the  students  of 
the  International  Correspondence  Schools.  Its  scope  may  be  seen 
from  the  following  table  of  contents  : 

Vol.  i.  Arithmetic,  mensuration,  algebra,  trigonometry,  loga- 
rithms, elementary  mechanics. 

Vol.  2.  Pneumatics,  gas,  petroleum,  heat ;  gas,  gasoline,  and  oil 
engines. 

Vol.    3.     Geometrical  and  mechanical  drawing.     43  pp. 

Vol.    4.     Gas  engineers'  tables,  and  formulae.     33  pp. 

Vol.    5.     Answers  to  questions.      197  pp. 


Diesel,  Rudolph. 

THEORY  AND   CONSTRUCTION  OF  A  RATIONAL  HEAT  MOTOR. 
Translated  from  the  German  by  Bryan  Donkin.     85  pp.     3  pi. 
London  and  New  York.      1894. 
Contains  the  full,  mathematical  theory  of  Diesel's  motor. 

Diesel,  Rudolph. 

DIESEL'S  RATIONAL  HEAT  MOTOR.     A  Lecture.     Pamphlet.     36 

pp.     3  pi.     New  York.      1897. 
A  description  of  the  engine  and  tests  made  on  it. 


ANNOTATED    BIBLIOGRAPHY!  293 

Donkin,  Bryan,  Jr. 

A  TEXT-BOOK  ON  GAS,  OIL,  AND  AIR  ENGINES  ;  OR  INTERNAL 
COMBUSTION  MOTORS  WITHOUT  BOILER.  i36illus.  419  pp. 
London.  1894. 

Part  i .  Gas  Engines  ;  contains  a  general  description  of  their  action 
and  mechanism,  and  a  classification  of  the  different  types.  The  his- 
tory of  the  gas  engine  occupies  four  chapters.  These  are  followed  by 
descriptions  of  the  various  makes  of  English,  French  and  German 
engines.  This  part  closes  with  chapters  on  gas  producers  and  on  the 
theory,  etc.,  of  the  engines. 

Part  2.  Petroleum  Engines  ;  contains  an  account  of  the  discovery, 
utilization  and  properties  of  oil.  Next  is  the  history  and  working 
methods  of  oil  engines,  followed  by  descriptions  of  the  different 
types. 

Part  3.  Air  Engines  ;  contains  their  theory  in  brief  and  descrip- 
tions of  various  makes. 

Elliott,  A.  G.  [Editor.] 

GAS  AND  PETROLEUM  ENGINES.  Translated  from  the  French  of 
Henri  de  Graffigny.  52  illus.  140  pp.  London  and  New 
York.  1898. 

After  chapters  on  the  history  and  the  principles  of  operation  of  gas 
engines,  various  foreign  makes  of  gas,  gasoline,  and  kerosene  engines 
are  described  and  illustrated. 

Fuel  gas  generators  are  treated  of  and  the  operation  of  engines  by 
them. 

The  final  chapter  is  on  the  care  and  maintenance  of  gas  and  oil 
engines. 

Goldingham,  A.  H. 

THE    DESIGN  AND   CONSTRUCTION  OF  OIL  ENGINES.     78  illus. 

196  pp.     New  York  and  London.      1900. 

A  \vork  on  kerosene  engines  proper.  Has  chapters  on  designing 
and  testing ;  on  water  tanks,  mufflers,  etc.  Treats  on  the  direct 
connection  of  engines  to  pumps,  etc.  Gives  instructions  for  engine 
running  and  repairs.  The  book  closes  with  a  description  of  various 
oil  engines. 


294  GAS   ENGINE   CONSTRUCTION. 

Goodeve,  T.  n. 

ON  GAS  ENGINES.     25  illus.     59  pp.     London.     1889. 
A   clearly  written   little   book,   descriptive   of  the  principles   and 
operation  of  the  Otto  engine  and  comparing  its  efficiency  with  the 
Lenoir  engine. 

Qrover,  Frederick. 

A  PRACTICAL  TREATISE  ON  MODERN  -  GAS  AND  OIL  ENGINES. 
123  illus.  256pp.  London  and  Manchester.  1897. 

A  short  historical  introduction  is  followed  by  a  chapter  on  the 
arrangement  of  the  engine  room.  Next  are  chapters  on  four  and  two 
cycle  engines  of  English,  French  and  German  builders  and  on  self- 
starters.  These  are  followed  by  the  practical  testing  of  engines  and 
computation  of  their  power  and  efficiency.  The  design  of  engines, 
producer  gas  and  products  of  combustion  complete  the  first  part  of 
the  book. 

The  second  part  consists  of  four  chapters  on  kerosene  and  gasoline 
engines  and  on  testing  them. 

Hiscox,  Gardner  D. 

GAS,  GASOLINE  AND  OIL  VAPOR  ENGINES.  Fourth  edition. 
270  illus.  361  pp.  New  York.  1901.  Published  by  Norman 
W.  Henley  &  Co.,  132  Nassau  Street,  New  York.  Price  $2.50. 

After  an  introductory  and  historical  chapter,  the  theory  of  the 
engine  is  clearly  explained  with  the  use  of  only  the  most  elementary 
mathematics.  Then  the  utilization  of  the  heat  of  the  fuel,  the  various 
losses  and  the  efficiency  are  treated  of.  A  chapter  is  on  their  economy 
when  used  to  operate  electric  lighting  plants.  This  is  followed  by 
one  on  the  values  of  various  gas  and  oil  fuels.  The  next  chapters 
treat  of  cylinder  capacity,  mufflers,  governors,  igniters,  and  lubri- 
cators. 

After  chapters  on  engine  management,  measurement  of  power, 
efficiency  and  testing,  is  one  of  157  pages  illustrating  and  explaining 
all  of  the  prominent  American  types  of  engines  and  showing  some  of 
their  applications. 

The  work  ends  with  a  chronological  index  of  the  gas  engine  patents 
in  the  U.  S.  Patent  Office,  and  a  directory  of  manufacturers  of  engines. 


ANNOTATED    BIBLIOGRAPHY^  295 

Hiscox,  Gardner  D. 

HORSELESS  VEHICLES,  AUTOMOBILES  AND  MOTOR  CYCLES 
OPERATED  BY  STEAM,  HYDRO-CARBON,  ELECTRIC  AND 
PNEUMATIC  MOTORS.  316  illus.  459  pp.  New  York.  1900. 
Published  by  Norman  W.  Henley  &  Co.,  132  Nassau  Street, 
New  York.  Price  $3.00. 

In  addition  to  a  large  amount  of  interesting  matter,  it  contains 
chapters  on  horseless  vehicles  with  explosive  motors,  electric  ignition 
devices,  atomizing  carbureters,  operating  devices  and  speed  gears, 
motive  power  and  running  gears,  automobile  bicycles  and  tricycles, 
gasoline  motor  carriages,  etc.  Contains  'also  reference  lists  of  auto- 
mobile patents  and  manufacturers. 

Humphrey,  Herbert  A. 

POWER-GAS  AND  LARGE  GAS  ENGINES  FOR  CENTRAL  STATIONS. 

ii  pi.     60  illus.     206  pp.     Westminster.     1901. 
A  reprint  of  the  Proceedings  of  a  Meeting   of  the  Institution  of 
Mechanical  Engineers. 

This  is  a  technical  work  on  engines  of  200  H.  P.  and  upward. 

Knight,  John  Henry. 

NOTES   ON   MOTOR   CARRIAGES,  WITH  HINTS  FOR  PURCHASERS 

AND  USERS.     15  illus.     84  pp.     London.     1896. 
Explains  the  principles  of  gas  engines  and  has  a  chapter  on  petro- 
leum carriages. 

Lee,  William  H. 

AMERICAN    AUTOMOBILE   ANNUAL.      103   illus.     275  pp.     Chi- 
cago.    1900. 

A   descriptive  pocket-book   of  the  prominent   types   of   horseless 
vehicles. 

Lieckfeld,  George. 

A  PRACTICAL   HANDBOOK  ON   THE   CARE   AND   MANAGEMENT 
OF  GAS  ENGINES.     Translated  by  G.   Richmond.       103  pp. 
Several  illustrations.     New  York  and  London.     1896. 
Treats  of  choosing  and  installing  an  engine  ;  of  testing  the  power 


296  GAS    ENGINE   CONSTRUCTION. 

of  an  engine.  Then  the  attendance  requisite  to  an  engine  is  men- 
tioned, how  to  stop  and  start,  and  the  proper  cleaning.  A  very  use- 
ful chapter  is  on  troubles  and  their  remedies.  The  next  one  is  on 
precautions  necessary  in  engine  running. 

The  final  chapter  is  on  gasoline  and  oil  engines. 

Lockert,  Louis. 

PETROLEUM  MOTOR-CARS.    92  illus.    218  pp.    New  York.    1898. 

Describes  not  only   kerosene  and  gasoline  motors,  but  also  steam 

engines  using  oil  fuels.     Both   foreign  and  American  machines  are 

shown.     The   two   final  chapters   are   on   acetylene   and   its   use   in 

motors. 

Longanecker,  E.  W. 

THE  PRACTICAL  GAS  ENGINEER.     2  illus.     119  pp. 
A  guide  to  the  selection,  setting  up  and  operation  of  gas  and  gaso- 
line engines.     Treats  in  a  comprehensive  manner  of  engine  troubles 
and  their  remedies. 

flacgregor,  William. 

GAS  ENGINES.     75  illus.     231  pp.     London.     1885. 

In  the  first  part  the  various  engines  are  taken  in  their  historical 
sequence  and  described. 

The  rest  of  the  book  is  occupied  with  the  theory  and  data  of  gas 
engines. 

The  illustrations  are  on  six  folded  plates  in  the  rear  of  the  volume. 

Norris,  William. 

A  PRACTICAL  TREATISE  ON  THE  ' '  OTTO  ' '  CYCLE  GAS  ENGINE. 

207  illus.     260  pp.     London,  1896. 

After  describing  the  Otto  engine  as  made  by  various  English  firms, 
there  follow  seventeen  chapters,  each  one  devoted  to  the  calculation 
and  design  of  a  different  part  of  the  engine. 

The  final  chapters  are  on  fuel  gas,  engine  testing,  and  private 
electric  lighting  plants. 


ANNOTATED  BIBLIOGRAPHY,  297 

Parsell,  Henry  V.  A.,  and  Weed,  Arthur  J. 

GAS  ENGINE  CONSTRUCTION.  146  illus.  300  pp.  New  York. 
1902.  Second  edition.  Revised  and  Enlarged.  Published 
by  Norman  W.  Henley  &  Co.,  132  Nassau  Street,  New 
York.  Price  $2.50. 

A  practical  handbook  for  the  amateur  mechanic  and  experimenter. 

Full  of  original  detail  drawings  and  half-tones  showing  the  mode 
of  pattern  making  and  of  finishing  and  assembling  the  castings. 
With  chapters  on  elementary  gas  engine  theory  and  design. 

Very  suitable  for  a  technical  school  manual  in  shop  work. 

Perry,  Prof.  John. 

THE  STEAM  ENGINE  AND  GAS  AND  OIL  ENGINES.    London.     1899. 

A  book  for  students  in  the  experimental  and  theoretical  investiga- 
tion of  the  action  of  these  engines. 

Roberts,  E.  W. 

THE  GAS-ENGINE  HANDBOOK.  40  illus.  241  pp.  Cincinnati,  (X 
1900. 

An  epitome  of  gas  engine  practice,  Treats  of  the  selection,  opera- 
tion and  care  of  engines.  Describes  various  details.  Gives  directions 
for  designing  and  testing.  Contains  also  several  practical  and  useful 
tables.  An  appendix  deals  with  two-cycle  engines  for  boats  and 
automobiles. 

An  excellent  book  for  the  designer  and  user. 

Roberts,  E.  W. 

How  TO  BUILD  A  THREE  HOUSE  POWER  LAUNCH  ENGINE.  14 
pi.  66  quarto  pp.  Cincinnati,  O.  1901. 

A  work  for  those  desiring  to  build  a  four-cycle  launch  engine  of 
3^  horse  power,  suitable  for  a  boat  20  to  25  feet  in  length.  Gives 
detail  drawings  and  directions. 


298  GAS    ENGINE    CONSTRUCTION. 

Roberts,  E.  W. 

ON  MARINE  AND  MOTOR  LAUNCHES.     20  illus.     107  pp.     New 

York.      1901. 

Gives  a  description  of  the  principles  of  operation  of  marine  gaso- 
line engines,  and  how  to  handle  them.  Contains  chapters  on  the 
properties  of  gasoline  and  on  choosing  an  engine. 

Robinson,  William. 

GAS  AND  PETROLEUM  ENGINES  :  A  PRACTICAL  TREATISE  ON 
THE  INTERNAL  COMBUSTION  ENGINE.  210  illus.  596  pp. 
London.  1890. 

About  one-third  of  the  book  is  occupied  wTith  detailed  descriptions 
of  various  engines,  arranged  both  historically  and  by  classes.  A 
chapter  is  devoted  to  various  modes  of  ignition. 

Directions  are  given  for  the  use  of  the  indicator  and  dynamometer 
in  power  measurements.  The  thermodynamics  of  the  gas  engine  are 
led  up  to  in  an  elementary  way,  and  give  the  theories  and  calcula- 
tions of  the  compression  and  combustion  of  the  charge.  The  various 
fuel -gas  producers  are  also  described. 

Stoddard,  E.  J. 

GAS  ENGINE  DESIGN.     14  illus.     31  pp.     Detroit.     1900. 
A  concise  treatise  on  the   leading    formulae   relating    to   the   gas 
engine  indicator  diagram,  and  to  the  subjects  of  vibration,   sreed, 
valves,  springs,  proportions  of  mixture,  sizes  of  parts,  etc. 

Wallis  Tayler,  A.  J. 

MOTOR  CARS  OR  POWER-CARRIAGES  FOR  COMMON   ROADS.     76 

illus.     200  pp'.     London.      1:897. 

Has  a  very  good  chapter  on  oil  engines  applied  to  vehicles,  and 
shows  various  details  of  different  makes. 

Warwick,  B.  P. 

THE  GAS  ENGINE.     How  TO  MAKE  AND  USE  IT.     Ljrnn,  Mass. 

1897. 
An    elementary  work   describing    various   makes   of   engines   and 


ANNOTATED    BIBLIOGRAPHY.  299 

giving  briefly  the  construction  of  a  two-cycle  engine.     Has  directions 
for  making  a  carbureter  and  an  electric  igniter. 

Westinghouse  flachine  Co. 

A  NEW  INDUSTRIAL   SITUATION.     12  illus.     24  pp.     Pittsburg. 

1900. 

Treats  of  the  economical  distribution  of  power  by  means  of  gas 
conveyed  in  pipes  from  large  gas-generating  stations,  and  shows 
its  utilization  by  Westinghouse  gas  engines  in  various  installations. 


INDEX. 


A  PAGE 

Adjusting  Contact  ... 232 

Adjusting  Exhaust  Valve 247 

Adjusting  Governor 242 

Adjusting  Igniter  Points 247 

Adjusting  Inlet  Valve  Spring 246 

Adjusting  Spring  Contacts 247 

Adjusting  Valve  Rod 216 

Advantages  of  this  Style  of  Governor 223 

Air  Passages,  Drilling  Inlet  Valve  Casing 

for 189 

Angle  Plate,  Description  of 83 

Angle  Plate,  Pattern  of . .     79 

Asbestos  240 

Asbestos,  Packing  Piston  with 239 

Assembling , 235 

Assembling  Crank  Shaft 236 

Assembling  Cylinder 235 


23? 
240 
197 
238 
237 
240 


Assembling  Engine  on  Bed  Plate 

Assembling  Governor 

Assembling  Inlet  Valve 

Assembling  Piston     , 

Assembling  Side  Rods  and  Bearings , 

Assembling  Valve  Rod  Bearings 

B 

Balancing  Fly-wheels 267 

Bearings,  Chucking     135 

Bearings,  Drilling  for  Keys 156 

Bearings,  l,ength  of 268 

Bearings  on  Angle  Plate 137 

Beau  de  Rochas  Cycle     24 

Bed  Plate,  Filing 159 

Bed  Plate,  Functions  of 262 

Bed  Plate,  Improved  Form 160 

Bed  Plate,  fining  up 159 

Bed  Plate,  Pattern  of 69 

Bibliography  of  Books 285 

Bibliography  of  Periodicals 291 

Books,  Bibliography  of 285 

Boring  Cylinder  Head  for  Valves 181 

Boring  Exhaust  Valve  Casing 201 

Boring  Exhaust  Valve  for  EX.  Pipe. ..  ...  201 

Boring  and  Finishing  Inlet  Valve  Casing.  187 

Boring  Piston  Castings  for  Piston  Pin no 

Boring  Tool 8> 


V  PAGE 

Caloric  Engines 12 

Carbureters .  253 

Carbureter,  Action  of..  ..   256 

Carbureter,  Connecting 256 

Carbureter,  Design  of 253 

Carbureter,  Fitting  up 255 

Carbureter,  Safety  Device  for 254 

Catch  Pins 240 

Centering  Tool  88 

Charge  of  Gas,  Proportion  of.. 249 

Chucking  and  Turning  Cylinder  Collar. .     96 

Chucking  Bearings 135 

Chucking  Connecting  Rod  Head 127 

Chucking  Cylinder  Head 175 

Chucking  Cylinder  Supports 142 

Chucking  Exhaust  Valve  Casing 201 

Chucking  Fly-wheels 163 

Chucking  Gas  Inlet  Ring. .     191 

Chucking  Inlet  Valve  Casing 185 

Chucking  Piston  Casting 107 

Chucking  Piston  End  of  Connecting  Rod.  121 

Chucking  Piston  Packing  Ring 116 

Chucking  Piston  Shell  1.05 

Circulating  Tank 248 

Class  i,  Engines  of 19 

Class  2,  Engines  of. 21 

Class  3,  Engines  of 22 

Class  4,  Engines  of  35 

Classes  of  Engines 19 

Classifications  of  Engine  Parts 261 

Clutch,  Starting  Handle 245 

Completed  Engine 241 

Compression  Space  263 

Connecting  Carbureter 256 

Connecting  Rod 121 

Connecting  Rod,  Chucking  Piston  End. . .  121 

Connecting  Rod  Ends,  Pattern  of 64 

Connecting  Rod  Head,  Chucking 127 

Connecting  Rod  Head,  Drilling.. 124 

Connecting  Rod,  fining  up 129,  239 

Connecting  Rod,  Proportions  of 269 

Connecting  Rod,  Turning  Steel  Center. . .   129 

Connec'ing  Rod,  Valve  Gearing 215 

Connecting  Water  Jacket 247 

Construction  of  Igniter 227 


3°2 


INDEX. 


PAGE 

Contact,  Adjusting 232 

Contact  Springs 230 

Cooling  Tank 248 

Counter  Weight  for  Fly-wheels 267 

Crank  Pin 171 

Crank  Pin,  Size 269 

Crank  Pin,  Valve  Gearing 214 

Crank  Pins,  Oiling 269 

Crank  Shaft 169 

Crank  Shaft,  Assembling ...  236 

Crank  Shaft,  Turning  Down    for   Gear 

Wheel 170 

Cycle,  Beau  de  Rochas 24 

Cylinder 93 

Cylinder,  Assembling 235 

Cylinder  Collar,  Drilling,  for  Side  Rods .     102 

Cylinder  Collar,  Jig  for 100 

Cylinder  Collar  Pattern 52 

Cylinder  Collars,  Chucking  and  Turning..    96 

Cylinder  Dimensions 262 

Cylinder,  Double-acting 32 

Cylinder,  Drilling  for  Cyl.  Head  Screws..  177 

Cylinder,  Hardwood  Mandrel  for 93 

Cylinder  Head,  Boring  for  Valves 181 

Cylinder  Head,  Chucking 175 

Cvlinder  Head,  Drilling  for  Igniter 228 

Cylinder  Head,  Drilling  for  Screws  ..  ..     175 

Cylinder  Head,  Location  of  Valves  in 178 

Cylinder  Head,  Pattern  of   58 

Cylinder  Head,  Position  of  Screws  in 178 

Cylinder  Head,  Size  of  Screws  for 271 

Cylinder  Lubricator 96 

Cylinder  Supports,  Chucking 142 

Cylinder  Supports,  Pattern  of 63 

Cylinder  Tubing 95 


Description  of  Angle  Plate 83 

Description  of  Governor 219 

Description  of  Valve  Gearing 213 

Design  of  Carbureter 253 

Design  of  Small  Gas  Engine 41 

Dimensions  of  Cylinders 262 

Diesel  Engine          38 

Double-acting  Cylinder    32 

Double  Cylinder,  Two  Cycle  Engine 37 

Draft  of  Patterns 51 

Drilling  Bearings  and  Cylinder  Supports 

for  Screws.. ." 144 

Drilling  Bearings  and  Side  Rods  for  Keys  156 

Drilling  Bearing  for  Gear  Stud 147 

Drilling  Connecting  Rod  Head 124 

Drilling  Cylinder  Collars  for  Side  Rods. .  102 
Drilling  Cylinder  for  Cyl.  Head  Screws. . .   177 

Drilling  Cylinder  Head  for  Igniter 228 

Drilling  Cylinder  Head  for  Screws    175 

Drilling  Exhaust  Valve  Casing  for  .Screws  207 
Drilling  Fly-wheel  and  Shaft  for  Pin 170 


PAGE 

Drilling  Fly-wheels  for  Crank  Pin     ...   . .  168 
Drilling  Inlet  Valve  Casing  for  Air  Pass- 
ages      189 

Drilling  Inlet  Valve  Casing  for  Gas  Holes  187 

Drilling  Lugs  on  Bed  Plate 237 

Drilling  Valve  Lever 209 


Electrical  Connections 229 

Electrical  Connections,  Testing 247 

End  Elevation  of  Finished  Engine 46 

Engine,  Assembling  on  Bed  Plate 237 

Engine  Details 261 

Engine,  Diesel 38 

Engine,  Double  Acting,  Two  Cylinder....  33. 

Engine,  Double  Cylinder,  Two  Cycle 37 

Engine,  Four  Cylinder 31 

Engin  e,  Gasoline 25. 

Engine,  Gunpowder 15. 

Engine,  Three  Cylinder 30 

Engine,  Two  Cycle 34,  36 

Engine,  Two  Cylinder 29 

Engines,  Caloric  12 

Engines  o  f  Class  i 19 

Engines  of  Class  2 21 

Engines  of  Class  3 22 

Engines  of  Class  4  35 

Engines,  Classes  of..  19 

Engines,  Classification  of  Parts 261 

Engines,  Four  Cycle  2333, 

Engines,  Historical 15 

Engines,  Hot  Air  . , 12 

Exhaust,  Muffler  for 282. 

Exhaust  Pipe,  Boring  Valve  Casing  for. ..  201 

Exhaust  Va  ve 201 

Exhaust  Valve  Casing,  Boring 201 

Exhaust  Valve  Casing,  Chucking 201 

Exhaust  Valve  Casing,  Drilling  for 

Screws 207 

Exhaust  Valve,  Grinding 204 

Exhaust  Valve  Lever  Pattern 78 

Exhaust  Valve,  Lining  up  with  Valve 

Rod 240 

Exhaust  Valve,  Patterns  of 76 

Exhaust  Valve,  Placing  in  Position.... 210,  240 

Exhaust  Valve  Spring 208- 

Exhaust  Valve,  Testing 247 

Exhaust  Valve,  Turning  and  Boring 204. 

Expansion,  Principle  of n 

Explosive  Mixture 249 


FacePlatePin 86 

Facing  up  Connecting  Rod  Head 128 

Fiber  Block 232- 

Filing  Bed  Plate 159 

Finished  Engine,  End  Elevation  of 46 


INDEX. 


303 


PAGE 

Finished  Engine,  Plan  of 44 

Finished  Engine,  Side  Elevation  of 43 

Finishing  Hubs  of  Fly-wheel 167 

Fitting  Governor 241 

Fitting  Igniter 242 

Fitting  up  Carbureter 255 

Fly-wheel  Constants  265 

Fly-wheel,  Drilling  for  Pin  170 

Fly-wheel,  Pattern  of 72 

Fly-wheels  and  Shaft,  Mounting..  ......  238 

Fly-wheels,  Balancing  ... 267 

Fly-wheels,  Chucking 163 

Fly-wheels,  Drilling  for  Crank  Pin 168 

Fly-wheels,  Finishing  Hubs 167 

Fly-wheels,  Rule  for  Weight  264 

Fly-wheels,  Turning  165 

Fly-wheels,  Turning  Tools  for 87 

Four  Cycle  Engines 23-33 

Four  Cylinder  Engine 31 

Q 

Gas  and  Air,  Proportions  of 249 

Gas  Engine,  Design  of  Small 41 

Gas,  Generating  from  Gasoline 249 

Gas  Inlet  Ring,  Chucking 191 

Gasoline  Engine        25 

Gasoline  Engine,  Inlet  Valves  of.. 27 

Gasoline  Gas 249 

Gasoline,  Generating  Gas  from 249 

Gasoline,  Precautions  in  Handling 258 

Gasoline,  Properties  of  255,  258 

Gas,  Proportion  of  Charge 249 

Gas  Pumping  Engine 21 

Gas,  Regulating  Supply 248 

Gear  Stud,  Drilling  Bearings  for 147 

Gear  Wheel,  Turning  and  Finishing 214 

Governor,  Adjusting 242 

Governor,  Advantages  of  this  Style  223 

Governor,  Assembling  ...: 240 

Governor,  Description  of % 219 

Governor,  Fitting 241 

Governor,  Otto  Type 28 

Governor  Patterns   78 

Governors,  Types  of  272 

Grinding  Exhaust  Valve 204 

Grinding  Inlet  Valve 191 

Gunpowder  Engine. 15 

H 

Hardwood  Mandrel  for  Cylinder 93 

Historical  Engines 15 

Horse  Power,  Rule  for  Finding 263 

Hot  Air  Engines 12 

I 

Igniter,  Construction  of 227 

Igniter,  Fitting 242 

Igniter,  Placing  in  Cylinder  Head     242 


PAGET 

Igniter  Points,  Adjusting 247 

Igniters,  Types  of 274 

Improved  Form  of  Bed  Plate ....  160 

Indentation  in  Valve  Rod 241 

Inlet  Port 271 

Inlet  Valve 185. 

Inlet  Valve,  Assembling 197 

Inlet  Valve  Casing,  Boring  and  Finishing  187 

Inlet  Valve  Casing,  Chucking 185 

Inlet  Valve  Casing,  Drilling  for  Gas  Holes  187 

Inlet  Valve,  Grinding 191 

Inlet  Valve,  Patterns  of 75 

Inlet  Valve  Stem 189 

Inlet  Valve,  Testing 246 

Inlet  Valve,  Turning  and  Drilling 189 

Inlet  Valves  of  Gasoline  Engine 27 


Jig  for  Cylinder  Collar 100- 


Keys  for  Side  Rods 154. 

Knuckle  Joint 214, 


length  of  Bearings 268. 

length  of  Piston 270. 

lining  up  Bed  Plate. 159 

L,ining  up  Connecting  Rod.   129,  239 

lining  up  Exhaust  Valve  with  Valve  Rod  240 

location  of  Valves  in  Cylinder  Head 178 

L,ubricator,  Cylinder 96 

lubricator  Pattern  78 

I^ugs  on  Bed  Plate,  Drilling 237 

n 

Main  Bearings,  Patterns  of 61 

Main  Shaft,  Size  of 267 

Mounting  Fly-wheels  and  Shaft 238 

Muffler  for  Exhaust  282 

Muffler,  Rule  for 282 


Oil  Cups... 147 

Oiling  Crank  Pins 269 

Otto  Type  of  Governor 28 


Packing  Ring 239- 

Packing  with' Asbestos 239 

Pattern  of  Angle  Plate 79 

Pattern  of  Bed  Plate 69 

Pattern  of  Connecting  Rod  Ends 64 

Pattern  of  Cylinder  Collars 52 

Pattern  of  Cylinder  Head 58 

Pattern  of  Cylinder  Supports. . . , 63 

Pattern  of  Exhaust  Valve  Lever 78 

Patterns 51 

Patterns,  Draft  of 51. 


INDEX. 


PAGB 

Patterns  of  Governor 78 

Patterns  of  Exhaust  Valve. 76 

Pattern  of  Fly-wheel 72 

Pattern  of  Lubricator 78 

Pattern  of  Piston  55 

Pattern  of  Piston  Packing  Ring 57 

Pattern  of  Starting  Handle 78 

Pattern  of  Valve  Rod  Bearings 74 

Patterns  of  Inlet  Valve     75 

Patterns  of  Main  Bearings 61 

Patterns,  Wood  for 51 

Periodicals,  Bibliography  of . 291 

Piston 105 

Piston,  Assembling 238 

Piston  Casting,  Boring  for  Piston  Pin no 

Piston  Casting,  Chucking 107 

Piston  Collar  for  Packing 115 

Piston,  Length  of 270 

Piston  Packing  Ring,  Chucking 116 

Piston  Packing  Ring,  Pattern  of 57 

Piston,  Pattern  of 55 

Piston,  Packing  with  Asbestos 240 

Piston  Pin,  Size  of 270 

Piston  Shell,  Chucking 105 

Plan  of  Finished  Engine 44 

Position  of  Exhaust  Valve 210 

Position  of  Screws  in  Cylinder  Head 178 

Precautions  in  Handling  Gasoline 258 

Principle  of  Expansion 1 1 

Properties  of  Gasoline 255,  258 

Proportions  of  Connecting  Rod 269 

Proportions  of  Gas  and  Air 249 

Pumping  Engine,  Gas 21 


Regulating  and  Starting 248 

Regulating  Gas  Supply 248 

Regulating  Speed  of  Engine..   222 

Rule  for  Counterweights  for  Fly-wheels  .  267 

Rule  for  Finding  Horse  Power 263 

Rule  for  Muffler 282 

Rule  for  Proper  Speed 263 

Rule  for    Weight   of    Gas    Engine    Fly- 
wheels   264 


Safety  Device  for  Carbureter 254 

Side  Elevation  of  Finished  Engine 43 

Side  Rods  and  Bearings,  Assembling 237 

Side  Rods,  Size  of ....  272 

Side  Rods,  Turning 151 

Size  of  Crank  Pin 269 

Size  of  Inlet  Port 271 

Size  of  Main  Shaft 267 

Size  of  Piston  Pin 270 

Size  of  Screws  for  Cylinder  Head 271 

Spark  Coil 229 


PAGE 

Special  Tools 83 

Speed  of  Engine,  Regulating 222 

Speed,  Rule  for  Proper 263 

Spring  Contacts,  Adjusting  247 

Spring,  Exhaust  Valve 208 

Spring,  Tempering , 208 

Starting.. 248 

Starting  Handle,  Fitting 245 

Starting  Handle  Pattern 78 

Starting  Handle,  Using 245 

Starting,  Regulating  and 245 


Table  of  Fly-wheel  Constants 265 

Tank,  Circulating 248 

Tank,  Cooling 248 

Tempering  Spring 208 

Testing  Accuracy  of  Work 154 

Testing  Electrical  Connections 247 

Testing  Exhaust  Valve 247 

Testing  Inlet  Valve 246 

Threading  Side  Rods 154 

Three  Cylinder  Engine 30 

Tool,  Boring 87 

Tool,  Centering 88 

Turning  and  Boring  Exhaust  Valve . .  204 

Turning  and  Drilling  Inlet  Valve 189 

Turning  and  Finishing  Gear  Wheel 214 

Turning   Down    Crank    Shaft    for  Gear 

Wheel 170 

Turning  Fly-wheels 165 

Turning  Side  Rods 151 

Turning  Steel  Center  of  Connecting  Rod.  129 

Turning  Tool  for  Fly-wheels 87 

Two  Cycle  Engine 34,  36 

Two  Cylinder,  Double  Acting  Engine  ...  33 

Two  Cylinder  Engine 29 

Types  of  Governors 272 

Types  of  Igniters 274 

V 

Valve  Gearing 213 

Valve  Gearing  Connecting  Rod 215 

Valve  Gearing  Crank  Pin .   214 

Valve  Gearing,  Description  of 213 

Valve  Lever 209 

Valve'Rod,  Adjusting 216 

Valve  Rod  Bearing,  Assembling.. 240 

Valve  Rod  Bearings,  Patterns  of 74 

Valve  Rod,  Indentation  in 241 

Valves,  Location  of,  in  Cylinder  Head. . . .  178 

Vaporizers 249 

w 

Water  Connections 247^ 

Water  Jacket,  Connecting 247 

Water  Jacket  Tube 94 

Wood  for  Patterns    51 


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Locomotive  Catechism, 

by    ROBERT    ORIN1SHA\V. 
22d  EDITION.  PRICE,  $2,00. 

Enlarged  by  Nearly  100  Additional  Pages,   Many  Illustrations, 

and  Three  Large  Folding  Plates. 

Containing  in  all  Nearly  450  Pages,  over  200  Illustrations,  and 
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This  book  commends  itself  at  once  to  every  Engineer  and  Fire- 
man, and  to  all  who  are  going  in  for  examination  or  promotion. 

In  plain  language,  with  full,  complete  answers,  not  only  all  the 
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which  old  hands  ask  as  ' '  stickers. ' ' 

It  is  a  veritable  Encyclopaedia  of  the  Locomotive,  is  entirely  free 
from  mathematics,  and  thoroughly  up  to  date. 

It  contains  Sixteen  Hundred  Questions  with  their  Answers. 

It  has  been  very  highly  endorsed  by  the  Journal  of  the  Brother- 
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Magazine. 

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and  Engineers.  The  book  is  a  veritable  encyclopaedia  of  the  Locomotive,  and  is  free  from 
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JUST  PUBLISHED. 


A    CATECHISM    ON    THE 

COMBUSTION  OF  COAL 


BY 


WILLIAM   M.  BARR,  M.   E., 

Author  of  "Pumping  Machinery,"    "Boilers  and  Furnaces,"  etc. 


FULLY  ILLUSTRATED. 


NEARLY  350  PAGES. 


Locomotive  engineers  and  firemen  will  find  this  BOOK  especially 
adapted  to  their  needs  while  preparing  for  examination  for  promotion.  It 
is  a  complete  guide  to  the  practical  solution  of  all  questions  relating  to  the 
combustion  of  anthracite  or  bituminous  coals  and  the  prevention  of  smoke. 

This  is  the  only  treatise  published  in  America  on  this  important 
subject.  It  should,  therefore,  have  a  place  in  the  working  library  of  every 
engineer*  fireman  and  student  in  engineering* 


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JUST  PUBLISHED. 

Fourth  Edition,  Revised  and  Much  Enlarged. 


Gas,  Gasoline  and  Oil  Engines 

By  GARDNER  D.  HISCOX,  fl.E. 


THE  ONLY  AflERICAN  BOOK  ON  AN  INTERESTING 
SUBJECT. 


365  Pages.    Large  Octavo,  Illustrated  with  270  Handsome  Engravings* 


PRICE, $2.5o. 


Full  of  general  information  about  the  new  and  popular  motive 
power,  its  economy  and  ease  of  management.  Also  chapters  on 
Horseless  Vehicles,  Electric  Lighting,  Marine  Propulsion,  etc. 

-    =-     -    SPECIAL  CHAPTERS  ON    =    =    = 

Theory  of  the  Gas  and  Gasoline  Engine,  Utilization  of  Heat 
and  Efficiency  of  Gas  Engines,  Retarded  Combustion  and  Wall 
Cooling,  Causes  of  Loss  and  Inefficiency  in  Explosive  Motors, 
Economy  of  the  Gas  Engine  for  Electric  Lighting,  The  Material 
of  Power  in  Explosive  Engines,  Carbureters,  Cylinder  Capacity, 
Mufflers,  Governors,  Igniters  and  Exploders,  Cylinder  Lubricat- 
ors, The  Measurement  of  Power,  The  Indicator  and  its  Work, 
Heat  Efficiencies,  United  States  Patents  on  Gas,  Gasoline  and 
Oil  Engines  and  their  Adjuncts  since  1875,  etc. 

List  of  the  Manufacturers  of  Gas,  Gasoline  and  Oil  Engines  in 
the  United  States,  with  their  addresses. 

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132  Nassau  Street,  New  York 


EDITION. 


TUB  Engine  Runners 

—  BY  — 

ROBKRT  GRIMSH  AW,  M.  K. 

Author  of  "  Steam  Engine  Catechism,"  etc. 

Telling  how  to  Erect,  Adjust,  and  Run  the  Prin- 
cipal Steam  Engines  in  use  in 
the  United  States. 


PRINCIPAL  FEATURES  OF  VARIOUS  SPECIAL  MAKES 

OF  ENGINES,  viz.: 

Armmgton  &  Sims,  Atlas,  Buckeye,  Cummer,  Eclipse- Corliss, 
Titchburg,  Fraser  &  Chalmers'  Corliss,  Frick-Corliss,  Greene, 
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TEMPER  CUT-OFF,  SHIPPING  AND  RECEIVING  FOUN- 
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SETTING,   CARE  AND    USE,    EMER- 
GENCIES, ERECTING  AND  AD- 
JUSTING SPECIAL 

ENGINES  : 

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Chalmers'  Corliss,  Gardner,  Harris-Corliss,  Ide,  New  Economizer, 
Phoenix,  Porter-Allen,  Porter- Hamilton,  Putnam,  Rollins,  Russell, 
Straight-Line,  Watertown,  Westinghouse,  Wheelock,  Whiting, 
Woodbury-Booth. 

Third     Edition.  366  Pages.  Fully  Illustrated. 

HANDSOMELY  BOUND  IN  CLOTH,  $2.00. 

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Eleventh  and  Enlarged  Edition,  Just  Issued. 

The  Steam  Engine  Catechism. 

By  ROBKRT  GRIMSHAW,  M.   K., 

Author  of  "  ENGINE  "RUNNER'S  CATECHISM,"  "LOCOMOTIVE  CATECHISM,"  Eleventh 
Edition,  "BOILER  CATECHISM,  "  "SHOP  KINKS,  "  etc.,  etc.,  etc. 


A  Series  of  Direct  Practical  Answers  to  Direct  Practical  Questions, 

Mainly  Intended  for  Young  Engineers  and  for  Examination 

Questions. 


NEARLY  1000  QUESTIONS  WITH  THEIR  ANSWERS. 

Two  Volumes  Bound  in  One  Volume,  413  Pages,  Fully  Illustrated, 

PRICE,  $2.00. 


What  is  said  of  this  book: 

UNITED  STATES  GOVERNMENT  ENDORSEMENT. 

NAVY  DEPARTMENT,  ) 

BUREAU  OF  STEAM  ENGINEERING,   | 

Washington,  D.  C. 

"  1  am  of  the  opinion  that  for  the  practical  instruction  of  students  and  young  en- 
.gineers,  Grimshaw's   '  Steam  Engine  Catechism  '   and  '  Engine  Eunner's  Catechism ' 
are  of  great  value,  besides  containing  many  points  ofuseto  those  older  in  the  profession. " 
(Signed)  G.  W.  MELVILLE,  Engineer-in-Chief,  U.  S.  A. 


"  A  valuable  work,  technically  correct  and  up  to  date.  Should  be  in  every  engineer's 
•hands. "— Marine  Journal. 

«  *  *  *  It  will  serve  admirably  as  a  guide  to  those  about  to  be  examined  for  a  license 
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in  the  science  of  Steam  Engineering,  will  find  profit  in  reading  the  '  Steam  Engine 
Catechism '  by  Eobt.  Grimshaw.  "—Mechanical  News. 

Lack  of  space  prevents  us  from  printing  hundreds  of  testimonials 
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JTJST    FTJJBJLjTSHIEXX, 

MECHANICAL   MOVEMENTS, 

POWERS,    DEVICES,   AND   APPLIANCES. 

By  GARDNER  D.  HISCOX,  fl.E., 
Author  of   "Gas,   Gasoline,  and  Oil  Engines." 

Svo.    Over  400  Pages.    1649  Illustrations,  with   Descriptive  Text. 
PRICE    $3.00. 

A  dictionary  of  Mechanical  Movements,  Powers,  Devices,  and  Appliances  with 
1649  illustrations  and  explanatory  text.  This  is  a  new  work  on  illustrated  mechanics, 
mechanical  movements,  de/ices,  and  appliances,  coveriner  nearly  the  whole  range 
of  the  practical  and  inventive  field,  for  tne  use  of  Mechanics,  Inventors,  Engineers, 
Draughtsmen,  and  all  persons  interested  in  mechanical  contrivances. 

SBJOTXO1VS. 

Section  I.  3Iechanical  Powers.— Weights,  Revolution  of  Forces,  Pressures, 
Levers,  Pulleys,  Tackle,  etc. 

Section  II.  Transmission  of  Power.— Ropes,  Belts,  Friction  Gear,  Spur. 
Bevel,  and  Screw  Gear,  etc. 

Section  III.  Measurement  of  Power.-Speed,  Pressure,  Weight,  Numbers, 
Quantities,  and  Appliances. 

Section  IV.  Steam  Power- Boilers  and  Adjuncts.-Eneines.  Valves  and 
Valve  Gear,  Parallel  Motion  Gear,  Governors  and  Engine  Devices,  Rotary  En- 
gines, Oscillating  Engines. 

Section  V.  Steam  Appliances.— Injectors,  Steam  Pumps,  Condensers,  Sepa- 
rators, Traps,  and  Valves 

Section  VI.  Motive  Power— Gas  and  Gasoline  Engines.— Valve  Gear 
and  Appliances,  Connecting  Rods  and  Heads. 

Section  VII.  Hydraulic  Power  and  Devices.— Water  Wheels,  Turbines. 
Governors,  Impact  Wheels,  Pumps,  Rotary  Pumps,  Siphons,  Water  Lifts.  Eject- 
ors, Water  Rams,  Dieters,  Indicators,  Pressure  Regulators,  Valves,  Pipe  Joints, 
Filters,  etc. 

Section  VIII.  Air  Power  Appliances.-Wind  Mills,  Bellows,  Blowers,  Air 
Compressor^  Compressed  Air  Tools,  Motors,  Air  Water  Lifts,  Blow  Pipes,  etc. 

Section  IX.  Electric  Power  and  Construction. -Generators,  Motors,  Wir- 
ing, Controlling  and  Measuring,  Lighting,  Electric  Furnaces,  Fans,  Search  Light 
and  Electric  Appliances. 

Section  X.  Navigation  and  Roads.— Vessels,  Sails,  Rope  Knots,  Paddle 
Wheels,  Propellers,  Road  Scraper  and  Roller,  Vehicles,  Motor  Carriages,  Tricy- 
cles, Bicycles,  and  Motor  Adjuncts. 

Section  XI.  Gearing.— Racks  and  Pinions,  Spiral,  Elliptical,  and  Worm  Gear, 
Differential  and  stop-Motion  Gear,  Epicyclical  and  Planetary  Trains,  "Fer- 
guson's "  Paradox. 

Section  XII.  Motion  and  Devices  Controlling  Motion.— Ratchets  and 
Pawls,  Cams,  Cranks.  Intermittent  and  St:>p  Motions,  Wipers,  Volute  Cams, 
Variable  Cranks,  Universal  Shaft  Couplings,  Gyroscope,  etc. 

Section  XIII.    Horological.— Clock  and  Watch  Movements  and  Devices. 

Section  XIV.  Mining.— Quarrying.  Ventilation,  Hoisting,  Conveying,  Pulver- 
izing, Separating,  Roasting,  Excavating,  and  Dredging. 

Section  XV.  3Iill  and  Factory  Appliances.— Hangers,  Shaft  Bearings,  Ball 
Bearings,  Steps,  Couplings,  Universal  and  Flexible  Couplings,  Clutches,  Speed 
Gears,  Shop  Tools,  Screw  Threads,  Hoists,  Machines,  Textile  Appliances,  etc. 

Section  XVI.  Construction  and  Devices.— Mixing,  Testing.  Stump  and  Pile 
Pulling,  Tackle  Hooks.  Pile  Driving.  Dumping  Cars,  Stone  Grips,  Derricks,  Con- 
veyor, Timber  Splicing,  Roof  and  Bridge  Trusses,  Suspension  Bridges. 

Section  XVII.  Draughting  Devices.— Parallel  Rules,  Curve  Delineators, 
Trammels,  Ellipsographs,  Pantographs,  etc. 

Section  XVIII.  Miscellaneous  Devices.— Animal  Power,  Sheep  Shears, 
Movements  and  Devices.  Elevators,  Cranes.  Sewing,  Typewriting  and  Pr.nting 
Machines,  Railway  Devices,  Trucks,  Brakes.  Turntables,  Locomotives,  Gas,  Gas 
Furnaces,  Acetylene  Generators,  Gasoline  Mantle  Lamps,  Fire  Arms,  etc. 

***  Prepaid  to  any  address  on  receipt  of  price 

NORMAN    W.    HENLEY   &   CO.,    PUBLISHERS 

132  NASSAU  STREET,  NEW  YORK 


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JUST    PUBLISHED. 

COMPRESSED    AIR 

ITS    PRODUCTION,    USES    AND    APPLICATIONS. 

BY   GARDNER    D.    HISCOX,    M.E. 
Author  of  «•  Gas,  Gasoline  and  Oil  Engines,"  "Mechanical  Movements,"  Etc.,  Etc. 

lyarge  Octavo.    820  Pages.    545  Illustrations. 
Bound   in   Cloth.   Price  $5.00.     Half  Morocco   Binding,   Price  $6.50. 


A  complete  treatise  on  the  subject  of  compressed  air,  comprising  its  physical  and 
operative  properties  from  a  vacuum  to  its  liquid  form.  Its  thermodynamics,  compres- 
sion, transmission,  expansion,  and  its  uses  for  power  purposes  in  engineering,  mining 
and  manufacturing  work.  Air  compressors,  air  motors,  air  tools,  air  blasts  for  cleaning 
and  painting.  The  sand  blast,  air  lifts  for  pumping  water,  oils  and  acids,  submarine 
work,  aeration  of  water,  railway  appliances  and  propulsion.  The  air  brake,  pneumatic 
tube  transmission,  refrigeration  and  cold  rooms.  The  hygiene  of  compressed  air,  its 
liquefaction  and  phenomena,  including  forty  tables  of  the  physical  properties  of  air,  its 
compression,  expansion  and  volumes  required  for  various  kinds  of  work,  and  a  list  of 
patents  on  compressed  air  from  1875  to  date. 

These  forty  air  tables  cover  most  of  the  relations,  of  our  atmosphere  and  its  con- 
tained moisture  in  its  various  conditions  from  a  vacuum  to  its  highest  pressure  and  its 
power  for  work  ;  its  final  liquefaction  and  the  phenomena  of  extreme  cold. 

The  tables  are  fully  explained  and  the  formulas  given  and  worked  out.  The 
thermodynarnic  formulas  for  air  compression  and  expansion  are  given  in  a  precise  form 
with  full  explanations  and  worked  out  examples,  so  that  anyone  can  solve  the  problems 
in  air  compression,  transmission,  expansion  and  the  power  required  in  atmospheric  work. 


CHAPTERS. 


CHAP.  I. 

II. 

III. 

IV. 

V. 

VI. 

VII. 

VIII. 

IX. 

X. 

XI. 

XII. 

XIII. 

XIV. 

XV. 

XVI. 

XVII. 

XVIII. 


Historical  Progress  of  Air  Work 

Physical  Properties 

Air  in  Motion  and  Its  Force 

Air  Pressure  below  Atmospheric  Pressure 

Flow  of  Air  Under  Pressure 

Power  of  the  Wind 

Isothermal  Compression  and  Expansion  of 

Air,  its  Law,  Diagrams  and  Formulas 
Thermodynamics 

Adiabatic  Compression  and  Expansion 
Compressed  Air  Indicator  Card 
Actual  Work  of  Compressor 
Multi-Stage  Air  Compression 
Expansion  of  Compressed  Air 
Transmission  of  Power  by  Compressed  Air 
Reheating  and  Its  Work 
The  Compressed  Air  Motor 
Efficiency  of  Compressed  Air  at  High  Alti- 
tudes 
Air  Compressors 


CHAP.  XIX. 

XX. 

XXI. 

XXII. 

XXIII. 

XXIV. 

XXV. 

XXVI. 

XXVII. 

XXVIII. 

XXIX. 

XXX. 

XXXI. 

XXXII. 

XXXIII. 

XXXIV. 

XXXV. 

XXXVI. 


Air  Compressors  of  Various  Makes— Con. 

Air  Compressors—  Continued 

Air  Compressors— Continued 

Compressed  Air  in  Mining,  Rock  Drills 

Pneumatic  Tools 

Pneumatic  Tools—  Continued 

Air  Pyrometer 

Compressed  Air  in  Railway  Service 

Pneumatic  Sheep  Shearing 

The  Compressed  Air  Blast 

Compressed  Air  in  the  Bessemer  Con- 
verter and  Blast  furnace 

Pneumatic  System  of  Tube  Transmission 

Compressed  Air  in  Warfare 

Compressed  Air  for  Raising  Water 

Refrigeration  by  Vacuum 

Hygiene  of  Compressed  Air 

Liquid  Air  and  Its  Generation 

A  list  of  patents  on  compressed  air 
from  1875  to  July,  1901. 


application. 


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